AUTO X – By Darkstars
Section 1 – FAQ’s
Section 2 – J-Body Advise
Section 3 – Modifications and Classifications
Section 1 – FAQ’s
What is an Autocross event?
Autocross/Solo II events are low to medium speed auto racing events; they are often run on parking lots and airport runways, although street events and events at Go Kart tracks sometimes take place. Generally a course will be defined using traffic cones. One driver at a time negotiates a course laid out with the cones, or pylons, testing their skill against the clock. Time penalties are charged for disturbing cones. In most regions, the penalty is 2 seconds per cone, although in some places it may be 1 second. There is an upper speed guideline for Solo II which is intended to keep speeds in a domain that most drivers might have encountered on the streets and highways; the fastest cars at a Solo II should not get much over 70mph. Generally, each driver takes three or four runs at an event. A driver is awarded the best time of all runs taken.
Are there other names for Autocross?
Solo II is the term the SCCA (Sports Car Club of America) uses to refer to SCCA-sanctioned autocross events. Gymkhana was the term used in much of the USA during the sixties. Now the term "gymkhana" as used in the USA usually connotes a gimmick event wherein drivers have to do odd things. Auto slalom is the term used in Canada.
Most autocrossers are driving/racing enthusiasts who enjoy motorsports competition. In fact, a large percentage of participants do not even own a "racecar"! They race the car they drive on the street. Some autocrossers are serious road race drivers who want to practice technique. Most are like you and me: laypeople with an itch for speed!
Autocross is an inexpensive, safe way to experience racing. It helps you discover your car's capabilities and limitations, making you a better, safer driver on the road. And it develops your own driving ability. Many would-be race drivers use it as a jump point into the sport of road racing. But probably the greatest thrill of autocross is the challenge of beating your own time. It's fun!
How much does it cost?
Costs vary widely around the country. Typical cost for a single day event is probably $25-$40. The sponsoring club has expenses like site rental and insurance. Costs for insurance are not insignificant in lawsuit-happy America. Keeping safe courses and speeds is important to the survival of the sport.
How do I join in the fun?
It costs almost nothing to start autocrossing, and since other cars are not on the course with you, there is almost no risk of damage to your car. To get started, just go to your nearest event. Ask questions, and if you brought your car with you, you might even be able to register and race right then and there! To find out where your nearest event is, subscribe to the mailing list, and post a message with the subject line "Hometown, State Events?" You should get at least one lead.
Can I watch for free? Can I bring a friend?
Autocrosses do not typically charge for spectators. Just go. You may be asked to sign an insurance waiver.
Do I have to join some club?
Membership in the organizing club is required in some places, but not necessary at most of the local events in the country. Check with the sponsoring club. However, membership has its benefits; event fee discounts, newsletter subscriptions, etc.
Do I need an SCCA license?
For autocross/Solo II events, no SCCA license is necessary. At the regional level, Solo II is very much a grassroots sport, but a few large SCCA Regions (San Francisco for one) require SCCA membership to participate. Check with your sponsoring club. At the Divisional and National level, drivers must be SCCA Members to compete.
What kind of car do I need?
Almost any car (or truck) will do, as long as it passes the tech inspection. Certain "tippy" vehicles such as Jeep Wranglers or Suzuki Sidekicks are not allowed because of the increased risk of rollover. People autocross everything from modified Porsches to stock Toyota Tercels to Lincoln Town Cars!
What are some guidelines of etiquette that I should follow?
-Do your work assignment.
-When you participate in an autocross, you are expected to be at your work post on time, and to perform your duties in full. Half-hearted efforts don't cut it. In fact, why not plan on volunteering for a major job at least once a year? Ask an organizer what jobs they need help with.
-Show up on time.
-Give yourself plenty of time to prepare your car, register, tech, and grid. No one likes it when latecomers rush up to the table and expect everyone to drop everything to help them. Being on time to the starting line is equally important; stay with your car while in the grid and be ready to go when the starter says GO!
-Be nice to newcomers.
-Offer advice or assistance. Lend one your pressure gauge. Make them feel welcome. Talk to them regardless of what they drive. A sociable attitude around novice drivers (no matter how good they think they are) goes a long way to better the sport and your future competition.
-Share your tools.
-Helping your fellow competitor in the spirit of good sportsmanship will give you a warm fuzzy feeling inside. Why not take it a step further: lend your car to someone whose ride has broken down!
-Respect others' pit locations.
-Stuff lying around in a parking space generally means someone is pitting there. Find an empty spot. Don't use 3 spaces when 2 will do. Finally, pick up your trash when you leave.
-Politely confront a suspected rules violation before filing a protest. It's no fun being surprised by an unexpected protest. Sometimes the offender isn't aware that what (s)he is doing is not allowed. Sometimes, what (s)he is doing is legal - and you should be doing it too!
-Be honest. If a course worker misses one of your downed cones, own up to it.
-Be a good winner/loser.
-Don't bother a driver who's about to take a run. You will ruin his/her concentration. A driver waiting in the grid won't appreciate it if you run up and ask him questions just before his run. Doing so breaks a driver's concentration, and generally results in mistakes on the course. So when you see drivers in the grid, helmet on, strapped in, don't bother them. If you must communicate, give the thumbs up sign.
-Don't speed in the pits or site entry road.
-Don't do burnouts before the starting line, don't do donuts in the parking lot, don't squirrel through the grid area. Unsafe practices like these put everyone at risk. Speeding or racing to and from events puts us all at greater risk of getting a speeding ticket, too! The cops know where we hold these things, after all! We don't need a bad reputation.
-Don't be stubborn. Be open to suggestions and don't think for a moment that you know everything. That kind of attitude is non-productive and usually painfully obvious.
-Don't make fun of someone else's car.
-Just because you hit a cone or two, don't get careless and plow down ten more. Somebody's got to right all those, you know! It slows things down, too.
-Don't yell at officials or course workers. They're volunteers you know. They don't need to take your crap. Cool down and come back when you can speak in a reasonable fashion.
-Don't cross banner lines. You know where you are and aren't allowed to go. That's what that tape's there for!
-Don't cheat. Don't steal. Don't drink. Don't litter.
-Be honest. Be compassionate. Be smart. Pick up your trash. Common decency is not a difficult thing!
What do I need to bring?
If your car is stock, and you intend to race it on your street tires, all you really need is your car, a helmet, a tire pressure gage, a cooler with drinks and snacks, VALID drivers license, painters tape to make numbers on the car, sunglasses, and your entry fee. Loaner helmets are usually available, and you can probably borrow a gauge. Always remember to empty everything out of your interior and trunk, you can not have ANY lose items in the passenger compartment, all change, pens, pencils, cigarettes, lighters, ect.. must be removed or secured in the glove box or center console, floor mats must be removed at well.
Who will I be competing against?
Your car will be grouped in a class of comparably equipped cars to make for relatively fair competition. If you are a novice, some events will report handicapped times so you can see how you fared against other novices no matter what they drove.
What are the different classes of competition?
These cars are fairly close to cars that are driven on the street, and are usually dual purpose automobiles. Permitted modifications include any DOT-approved tire, any shock that attaches to the stock mounting points, any exhaust from the catalytic converter back (subject potentially to local sound control), any brake pads, any front sway bar, any wheels of stock dimensions and offset, and addition of a race harness. Cars prepared to Road Racing Showroom Stock rules are permitted to run in Stock, but are not permitted to "mix" rules between the two classes. The stock class is split up into sub-classes organized by performance. They are lettered A thru H, in an approximate order of descending performance. There is also a class called Super Stock (SS). Examples of cars in A-Stock (AS) include: Porsche 911's, Turbo MR2's, etc. The most populated class appears to be C-Stock (CS), which includes Miatas and many BMW's. At other end of the spectrum, H-Stock (HS) includes cars with relatively low power-to-weight ratios like the Toyota Tercel and Honda Accord. F-stock is a class that is generally populated with the "pony cars" such as Camaros, Firebirds, and Mustangs.
Street Touring (ST)
This is a new category of street cars modified more broadly than allowed by Street Prepared rules. It includes 4-seater sedans with specific displacement limits, aimed at cars modified using common suspension, engine, and appearance parts which are fully legal and compatible with street use anywhere in the country. Street Tires are required (DOT wear rating of 140 or better).
Street Prepared (SP)
Street Prepared cars are allowed significant modifications over stock, but many are still dual-purpose cars. Some of the permitted modifications are: any legal modification in stock; any springs that fit stock attachments; any sway bars; any wheels & DOT-approved tires; any induction for the engine (except that cars that were originally normally aspirated must remain normally aspirated); and any exhaust including headers. Compression ratio and camshafts in the engine must remain stock. Cars prepared to Road Racing Improved Touring and American Sedan rules are permitted to run in Street Prepared, but as with Showroom Stock, rules "mixing" is strictly prohibited.
Prepared cars are allowed very substantial modifications; Prepared cars are rarely licensed for street use. Interiors may be gutted, cams and pistons are free, and suspensions may be significantly modified. Cars prepared to Road Racing GT and Production rules are permitted to run in Prepared.
Street Modified (SM)
Street Modified is a new category for street able cars modified beyond Street Prepared allowances. The rules are simple, and almost anything goes. Cars must be legally registered for the street.
The Modified category is split into parts. A, B, and C Modified consist of purpose-built racing cars, usually Formula Cars, Sports Racers, or "Specials". Usually these are open-wheel, single-seat cars without fenders. D and E Modified are for very heavily modified production cars. In these classes, basically anything goes except that you must retain the original floor pan and driveline layout (a front-engine car cannot become a rear-engine car). D Modified is for cars with engines less than 2 liters, and E Modified is for cars with engines greater than 2 liters.
Most clubs offer a separate class in which women can compete in addition to the overall competition. This is signified by the letter L being added to the classification on the car. For example, CSP-L.
Street Tire (ST)
Many clubs offer a separate class in which cars fitted with street tires (as opposed to Racing based, or R- tires) can compete in addition to the overall competition. Cars from any, or at least most, open classes compete together and their times are handicapped using some indexing scheme. A common index is the RTP/PAX index, and this sort of indexing is sometimes called PAXing. This is signified by the letter ST being added to the classification on the car. For example, CSP-ST.
Novice (N) aka Rookie (R)
Again, most clubs offer a separate class in which newcomers can compete in addition to the overall competition. This is signified by the letter N being added to the classification on the car. For example, FS-N. Most clubs also rank the novices' driving performance using a handicap-like system that tries to account for differences in car performance.
How should I prepare my car for a race?
Your car should be well maintained at the very least. Keep up with oil/fluid changes, brake inspections, valve adjustments, etc. One particularly important part is the timing belt. Make sure it has been changed within the recommended service period. The high revs your engine will experience in a run are likely more than an old belt can take. Check your fluid levels. Clean out your car. Remove everything that you won't need, and take out everything you brought with you before you race. As part of the tech inspection, officials will make sure there won't be anything flying around your cabin while you're on the course. You also might want to wash your car and the engine compartment if you haven't done so in months. Embarrassing! Just before you get to the autocross site, stop at a service station and pump up your tires to 42 psi or so. It sounds high, but you will need extra air in those tires to prevent them from rolling over onto the sidewalls during hard cornering. When you get to the site, as a novice you might ask someone who looks like (s)he knows what (s)he is doing how much air you'll probably need. Then let out the air until you've achieved that pressure. It's easier to let air out than to pump it in! (Some events provide air via a compressor or air tank/bubble.)
What is a tech inspection?
A mandatory pre-race safety inspection of your car.
What can I expect at a tech inspection?
Cars are checked for safety at each event before your first run. Generally, this task falls to an experienced autocross driver and the inspection is friendly. Your car must have a working seat belt, a good return spring on your throttle linkage, working brakes, a securely fastened battery, tight lug nuts, well-packed bearings, no excessive play in your suspension, and an interior free of loose articles. Street tires must have measurable tread depth and no cord showing. Any street car in reasonably good condition should pass this quick inspection without any trouble. Often, cars are inspected ("tech'd") at a specific tech area before being allowed on the starting grid, but occasionally cars are tech’d on grid. Very often cars in the first run group of the day are tech’d on grid for efficiency.
Section 2 – J-Body Advise - (Note: This is all based on MY opinion)
Let be brutally honest, stock cav's aren't really considered competitive. Rear drums, twist beam rear suspension, no rear sway bar, needs to be lowered, factory tires suck, ABS isn’t standard, lack of power, ect... Not saying a cav can't be competive, it definitely can be, with some practice and driving skills, but car for car spec for spec there’s a lot of cars that are far better, for example, you add an intake, lower it, exhaust, ect... any ONE of those mods puts you in STS class, where you'll be up against modded Celicas, RSX's, Integras, Civics, basically all the import sport compacts, which in many ways stock for stock are superior cars, independent 4 wheels suspension, 4 wheel disk, a lot come with a "sport suspension" option of some sort even when stock, more powerful, ect... biggest advantage all of those cars have over us is the aftermarket, the suspension parts available for the Hondas is infinite which helps when you can't run any custom parts in STS class. If you mod a cav far enough to get past is inherent flaws, for example, rear disk brake swap, it puts you in modified class instead of street touring, if you end up in a modded class you have absolutely zero chance of being competitive with a cav. But like I said some skill and practice and some basic mods and you should be alright, if your going to auto x competitively and get real into it a cav is not the car of choice, if your going out because you want to have fun any car will do. I've said it before and I'll say it again, auto X is the most fun you can have in a car.
My biggest things of Advise for people starting off....
1- Walk the course.
When you get there and register they let you walk a laps around the course, DO IT.
2- Take the school.
At the beginning of the season they have a school, go to it. It’s like a driving school thing. Because no matter who good you THINK you are you will be amazed at the cars that will whoop your ass, older completely stock @!#$ boxes will beat you peaty bad hahaha, sad but true, everyone thinks they are a good driver, you don't realize how unskilled you really are till you try auto crossing hahaha.
3- Drive SMOOTH.
It may feel faster to go hauling ass sliding around barely making corners ect... but a nice smooth line will get you faster times. In a J-body or any other low power FWD car the key is running smooth, not running hard, brake early on consistently through corners. If you enter a corner hard, slam the brakes and try to power out of the turn you’re going to lose time. We don’t have the power to be able to do that successfully, instead your best bet is stay smooth and even and try to carry as much speed as possible through the corner, rather then lose it and try to regain it.
4- Learn to Slalom.
You will suck at slalom till you figure it out, when going through don't keep hitting gas and brakes, find a nice spot on the throttle and stick with it, maintain a smooth speed through. Also when actually coming around one cone to the next, start turning before you get to the cone, it takes time to actually get the wheels turned the opposite direction plus the car will not turn when you start turning, it will transfer all the weight from one side to the other before the vehicle actually turns, granted the weight transfer and physically turning the wheel doesn't take long but it takes long enough that you want to start turning before the next cone. If you don't your not going to be fast through the slalom, instead of a nice curve in and out you will be making a sharp cornered zigzag and at a lot slower of a speed.
General Driving Tips
Seat time, seat time, seat time. That's the best way to go faster. They say, "Before you fix the car, fix the driver". That's because there's so many techniques to improve your driving, it takes seat time to learn them all, but once you do, someone without those skills would have to spend a lot of money on their car to beat you, and probably still couldn't.
Here are a few techniques to get you started. Don't try to apply them all in your first run, you'll be too busy. But read through the whole list, then work at gaining these skills one at a time.
I can't emphasize this enough. I repeat it out loud while I am driving. It's so easy to forget, but makes such a big impact on my driving. It all relates to hand-eye (and eye-foot) coordination. Look where you want your hands to drive you, and look far enough ahead to take advantage of the feedback. If you're looking at that outside cone that you're afraid you'll hit, well, you'll hit it. If you're looking ten feet in front of the bumper, the turns will keep surprising you. Imagine looking at your feet while you are running on foot! You won't be very coordinated, and you won't have a good sense of distance or speed. Same goes for driving hard corners as you do in autocross. Look ahead. You will be astounded at your performance the first time you remember to do this all the way through a course.
Slow Down to Go Fast.
A common problem when you're starting out is trying to take the tight sections too fast, and not staying in control. I still remember finishing a run and saying, "Well, I didn't go very fast, but it sure was smooth," only to find out I'd gone faster by a full second! Just be patient in the slow spots. They're slow spots, after all.
Brake hard in corners.
Go ahead, squeeze the brakes hard. There's no morning coffee on your dashboard, or eggs in the front seat. Once you decide to slow down for the corner, don't waste any time. If you find yourself at a crawl and you're not at the corner yet, why, you've just found out that you can brake later. Locking up your tires will not make you stop faster, so squeeze the brakes and let them do the work, not your tires.
Don't ask too much of your tires. For any tire/pavement pair, there's only a certain amount of traction. We'll call that 100% traction. You can use up that traction with your throttle, your brakes or your steering wheel. So if you're going into a corner, using 100% of your traction to make the turn, what happens when you ask for more traction by applying the brakes? Either you won't brake or you won't turn. Or both. Same goes for accelerating out of a corner. Ease in the throttle as you ease out of the turn. So use full throttle and full braking only in a straight line. This goes back to slowing down to go faster, and brings us to...
You may have noticed that I used the phrases "squeeze the brakes" and "ease in the throttle". This is where you have to change your mind-set about inputs to controlling your car. You need to convince yourself that you can make your car respond better by squeezing the brakes hard instead of standing on the brakes, by rolling in the throttle rapidly instead of stomping on the gas, by turning the wheel quickly instead of cranking it around. Subtle, but it will show up in how often your car is in control instead of scrubbing off speed pushing around a corner. And it will take a lot of practice to become second nature.
Shift near redline.
On the street, we don't usually shift near redline (high rpms). But in autocross, you want to be making the most of the power available to you. You'll learn to hear the motor as you drive and stay in a low gear longer. Most courses will be in second gear for stock cars. If you're shifting to third, you're shifting too soon, and giving up power (ask local drivers if this is true in your region).
Focus on driving.
Don't worry about the blinkers, wipers or horn. You're bound to hit them as you drive. Don't let it throw you. We've all done it!
More, Later... There are many more techniques for getting better times, but start with the ones listed above. After you've learned them, you'll be ready to buy a book on autocrossing or attend a driver's school and learn the advanced techniques of heel/toe, shuffle steer, late apex, and more.
Secrets of Solo Racing
by Henry A. Watts
How to Make Your Car Handle
by Fred Puhn
Section 3 – Modifications and Classifications
Comparison of permitted modifications in SCCA classes
Heres the link since you can't post in table format
Note on using this list:
• This list is not a replacement for the rulebook. It is intended as a rough guide to answer questions of the type "My car has the following mods.... What class is it in?" The details should always be referred to the SCCA Solo II rulebook and the updates published in FasTrack.
• Each item listed "Y" is something that is permitted. More may be permitted for that prep level so check carefully.
• Remember the use of "update/backdate" and "option package swap" in the general section of the rules. A modification may not be listed as "legal" in the lower sections but still be permitted because of those provisions. Likewise, "modifications" authorized in factory Technical Service Bulletins for non-competition purposes are also legal.
The biggest classes are Stock and STS, here is the detailed rules for modification for those to 2 classes per SCCA rules
Cars running in Stock Category must have been series produced
With normal road touring equipment capable of being licensed for
Normal road use in the United States, and normally sold and
Delivered through the manufacturer’s retail sales outlets in the
United States. Car models not specifically listed in any Stock
Category class must have been produced, and must meet the above
Requirements and been sold through normal U.S. dealerships, in
Quantities of at least 1,000 in a 12- month period in order to be
Eligible for the Stock Category.
Except for modifications authorized below, Stock Category cars
must be run as specified by the factory with only standard
equipment as defined by these Rules. This requirement refers not
just to individual parts, but to combinations thereof which would
have been ordered together on a specific car. Any other
modifications or equipment will place the car in Street Touring,
Street Prepared, Street Modified, Prepared or Modified Categories
as appropriate. Configurations involving damaged parts (e.g.,
blown fuses) are not typically authorized by the manufacturer and
hence are not allowed.
Option package conversions may be performed between specific
vehicles of a particular make and model, but only between
configurations from within a particular model year. Such
conversions must be totally complete and the resultant car must
meet all requirements of this Section. Alternate parts listed in a
factory parts manual are not authorized unless their use is
specifically referenced in the factory service manual or in a service
bulletin for the specific model.
See Sections 3.8 and 8.3 for documentation requirements.
Alternate components which are normally expendable and
considered replacement parts (e.g., engine and wheel bearings,
seals, gaskets, filters, belts, bolts, bulbs, batteries, brake rotors,
clutch discs, pressure plates, suspension bushings, drivetrain
mounts, etc.) may be used provided they are essentially identical to
the standard parts (e.g. have the same type, size, hardness, weight,
material etc.), are used in the same location, and provide no
performance benefit. The allowance for use of such replacements
does not include camshafts, differential covers, or ring-and-pinion
sets, nor does it authorize the use of piston rings having different
configurations (e.g. “Total Seal”) from those of the original.
Hardware items (nuts, bolts, etc.) may be replaced by similar items
of unrestricted origin. Safety wire, threadlocker compounds, and
locking nuts are permitted. These allowances are strictly to allow
components to be replaced from alternate sources other than the
original manufacturer. They should not be construed as an
allowance to replace components with those which could be
considered a ‘higher performance’ alternative. Parts available as
replacements through the dealers parts department, the factory, or
any other source which do not meet standard part specifications
(e.g., hardness, size, etc.) are not legal in Stock Category, except as
specifically provided elsewhere in these rules.
Cars listed as eligible in and prepared to the current national
Showroom Stock Club Racing rules are permitted to compete in
their respective Solo Stock Classes. This does not include
Showroom Stock cars with installations of post-factory
“performance packages” otherwise known as “trunk kits”. Neither
Showroom Stock nor Solo Stock cars are permitted to interchange
preparation rules. Showroom Stock cars may use tires which are
eligible under current SS rules, even if they are not eligible in Stock.
Specific vehicle classifications are located in Appendix A of these rules.
13.1 AUTHORIZED MODIFICATIONS
If a modification is not specifically authorized in this or previous
sections of these Rules it is not allowed. It is not permitted to use
illegal parts even if they have been set to stock specifications.
Refer to Appendix F for past clarifications of these rules.
A. Accessories, gauges, indicators, lights and other appearance,
comfort and convenience modifications which have no effect on
performance and/or handling and do not materially reduce the
weight of the car are permitted. This does not allow driver’s seat
substitutions, or the removal of “tow hooks”, a.k.a. “tie-down
loops”. Delayed shutdown devices such as the “Turbo Timer”,
which perform no function while the car is in motion, are permitted.
This does permit the installation of an additional mirror
(e.g. a “Wink”), but does not allow the removal of the original
mirror. “Grounding kits” specifically designed to support sound
systems are permitted but may serve no other purpose.
B. Hood straps or fasteners may be added.
C. Any fuel tank cap may be used.
D. Windshields may be folded (but not removed) provided the
required mechanism is standard equipment.
E. Alternate steering wheels are allowed, provided the outside
diameter is not changed by more than one inch from the standard
size. Steering wheels with an integral airbag may not be
F. Spare tires, tools and jacks may be removed. Any fastening
hardware and/or other pieces that can no longer be firmly secured
in the absence of the spare tire may be removed if necessary
to ensure compliance with 3.3.3.B.1.
G. Roll bars and roll cages may be added (See Appendix C). It is
strongly recommended that roll cages be constructed according
to Section 18 of the GCR, though they must be bolted (not
welded) into the automobile and be contained within the driver/
passenger compartment. Roll bars may be welded in. A roll
cage has more than four attachment points to the body or frame,
or has bracing both fore and aft of the main hoop.
H. Driver restraints as outlined in Section 3.3.1 are allowed. Seats
may not be cut to allow for the installation of alternate seat belts
or harnesses. Passive restraint systems may not be removed. A
horizontal “harness bar” may be used as part of the installation
hardware for allowed driver restraints. It may serve no other
purpose (e.g., structural enhancement).
I. Cars may add one rear trailer hitch. The resulting weight addition
is allowed. The hitch may serve no other purpose. Factory
tie downs may be removed to facilitate hitch installation.
J. Tow bar brackets may be installed but may serve no other purpose.
K. Any item that cannot be held permanently in place by factory
installed fasteners may be removed.
Any tire which is OE on a car eligible for Stock Category may be used.
Non-OE tires must meet the following requirements to be eligible for
use in Stock category:
A. The tire must not appear on the following list, which may be
altered at any time by the SEB upon notification of membership.
No tire models are currently listed.
B. No tire models will be approved for competition during the rest
of the year after April 30 of each calendar year. Each eligible tire
model must meet all requirements of Section 13.3 by April 30,
and must continue to meet them thereafter. A tire model will
normally be determined by the designation in the Tire Guide.
However, any of the following changes or similar changes (as
determined by the SEB) will also be considered to represent a
new model for eligibility purposes, even if the designation does
not change: change of tread pattern at either full or partial tread
depth; characterization by the manufacturer or distributor of a
tire as “new” after April 30.
A tire model which was previously allowed by these rules continues
to be legal until specifically disallowed. This follows
years of precedence on eligibility for discontinued tire models.
If a manufacturer reintroduces a tire model which was previously
discontinued, that tire will be considered a new model.
Therefore, it will have to meet the rules specified in SR Section
13.3 including the April 30 introduction date.
C. The model of tire must be listed in a current or previous two
years of the Tire Guide and Tread Design Guide, or otherwise be
approved by the SEB. The tire model must have Department of
D. Within each tire model, the sizes which are available must be
equally available to all competitors. Tire model variations differing
from standard specification, delivered only on a limited
basis, or only to selected competitors, may not be used.
E. No racing tire or recap (on any casing) may be used.
F. Each tire model must be sold in at least four rim diameters, with
a total of at least six sizes.
G. Tire must fit the allowable wheels and fender wells without
H. Each tire must have non-zero measurable tread depth (i.e.,
points where it is possible to obtain positive measurement values)
as described in Section 3.3.D. Tires may not have cord
visible at any time during competition.
Any type wheel may be used provided it complies with the
following: it is the same width and diameter as standard, and as
installed (including wheel spacers if applicable) it does not have an
offset more than +/- 0.25 inch from a standard wheel for the car.
The resultant change in track dimensions is allowed.
Wheel spacers are permitted, provided the resultant combination
complies with the offset requirements of this section. Wheel studs,
lug nuts, and/or bolt length may be changed.
Vehicles equipped with rims having metric specifications may use
alternate rims as determined by using the following procedure:
Diameter: converting the metric measurement to inches and
using the nearest smaller inch diameter rim.
Width: converting the metric measurement to inches and using
the nearest smaller 1/2-inch width rim. Offset and track must
still comply with the requirements of this section.
13.5 SHOCK ABSORBERS
A. The make of shock absorbers may be substituted providing that
the number, type (e.g., tube, lever, etc.), system of attachment
and attachment points are not altered, except as noted below.
The interchange of gas and hydraulic shocks absorbers is permitted.
The following restrictions apply:
1. No more than two separate external shock damping adjustment
controls. This permits the use of shocks which originally
came with more than two external adjustments, which
have been converted to double-adjustable, only if the additional
adjustment controls have been permanently disabled
(e.g. via welding, epoxying, grinding off). Gas pressure
adjustment is not considered a damping adjustment.
2. Suspension geometry and alignment capability, not including
ride height, may not be altered by the substitution of alternate
3. Adjustable spring perches are allowed, but the spring loadbearing
surface must be in the same location relative to the
shock mounting points as on the standard part. Shims may
be used to achieve compliance.
4. The fully extended length must be within plus or minus one
inch of the dimension of the standard part.
5. Electronically controlled shocks may not be used on vehicles
not originally equipped with such units. Vehicles originally
equipped with electronically controlled shocks may use the
standard parts or non-electronically controlled alternative
shocks subject to all the requirements of 13.5. Non-standard
electronically controlled shocks are not allowed.
B. The mounting hardware shall be of the original type. The use of
any shock absorber bushing material, including metal, is permitted.
Pressed or bonded bushings may be removed from standard
parts to facilitate the use of alternate bushings which fit in
the original location without alterations to the part. This does
not permit the use of an offset shock bushing. A shock absorber
bushing may be implemented as a spherical bearing. The bushing
attaching the end of a strut to the body or frame on a strut
type suspension is a suspension bushing, not a shock bushing.
C. To facilitate the installation of commonly available aftermarket
shock absorbers, struts, or strut inserts whose shaft size is larger
than the center hole of an upper shock mount assembly, that
hole may be enlarged by the minimum necessary to accommo64
date the shock shaft size, provided the following restrictions are
met: (1) the enlarged hole must remain concentric with the original
configuration; (2) the enlargement of the hole does not require
modification of a bearing (as opposed to a washer, sleeve,
or plate); (3) neither the hole enlargement not the location of the
shock shaft changes any alignment parameter. Provided these
constraints are met, this permits enlarging of the center hole in
an upper shock mount with an integrated rubber bushing, where
the bushing is integral to the mount and bonded to the plate and
the mount is provided by the OEM as an assembly. This includes
drilling out and/or removal of the metal sleeve.
A bonded shock bushing/plate assembly is considered a shock
mount assembly and not a bushing. It may not be replaced with
an aftermarket performance part. It is not permissible to replace
the bonded bushing material.
D. A suspension bump stop is considered to be performing the
function of a spring. Therefore, the compressed length of the
shock at the initial point of contact with the bump stop may not
be increased from the standard part, although the bump stop
may be shortened for the purpose of installing non-standard
shocks. Bump stops installed externally and concentric with the
shaft of a shock may be drilled out to fit a larger diameter shock
shaft. Bump stops may be substituted for the purposes of installing
E. A hole may be added through the bodywork to route the line
from the reservoir to the shock absorber body. Such holes may
serve no other purpose.
F. A hole my be added to an interior body panel to provide access
to the adjustment mechanism on an allowed adjustable shock
absorber. The hole may serve no other purpose. Interior panels
are defined to be those pieces which cover the interior of the
vehicle and are accessible from inside the vehicle. They do not
include structural panels, such as wheel wells or inner fenders,
which may also be accessible from inside the car but which
actually form part of the body of the vehicle.
A. The make and material of brake linings may be changed.
B. Substitution of clutch and brake hydraulic lines with solid metal
or braided metal is allowed on all cars manufactured before
model year 1992.
C. Alternate brake bleeder fittings such as “Speedbleeders” are
permitted. They may serve no other purpose.
13.7 ANTI-ROLL (SWAY) BARS
A. For front anti-roll (sway) bars:
1. Substitution, addition or removal of any front anti-roll bars is
2. Substitution, addition or removal of anti-roll bars may serve
no other purpose than that of an anti-roll bar.
3. The use of any bushing material is permitted.
4. No modification to the body, frame or other components to
accommodate anti-roll bar addition or substitution is allowed,
except for the drilling of holes for mounting bolts. Nonstandard
lateral members which connect between the brackets
for the bar are not permitted.
B. Rear anti-roll (sway) bars:
1. May not be removed, replaced, or modified in any way.
Standard, as defined herein, suspension springs must be used.
They may not be cut, shortened or collapsed. Cars with swing axle
suspension may be lowered sufficiently to achieve no more than
two degrees of negative camber at rest, and may use a camber
Both the front and rear suspension may be adjusted through their
designed range of adjustment by use of factory adjustment
arrangements or by taking advantage of inherent manufacturing
tolerances. This encompasses both alignment and ride height
parameters, if such adjustments are provided by the stock
components and specified by the factory as normal methods of
adjustment. However, no suspension part may be modified for the
purpose of adjustment unless such modification is specifically
authorized by the factory shop manual for non-competition
Suspension bushings, including but not limited to those which carry
the weight of the vehicle and determine ride height, may not be
replaced with bushings of a different material or dimension.
Replacement control arms for vehicles having integral bushing/arm
assemblies must be standard factory parts as per Sections 12.4 and
If authorized by the manufacturer, the use of shims, special bolts,
removal of material to enlarge mounting holes, and similar
methods are allowed and the resulting alignment settings are
permitted even if outside the normal specification or range of
specifications recommended by the manufacturer. If enlarging
mounting holes is specifically authorized but no material removal
limits are specified, material removal is restricted to the amount
necessary to achieve the maximum factory alignment specification.
13.9 ELECTRICAL SYSTEM
A. The make of spark plugs, points, ignition coil and high tension
wires is unrestricted including spark plug wires having an in-line
B. On cars made prior to January 1, 1968, any ignition system
using a standard distributor without modification may be used.
C. Ignition settings may not be adjusted outside factory specifications.
D. No changes are permitted to electronic engine management
systems or their programming.
13.10 ENGINE AND DRIVE TRAIN
A. The engine air filter element may be removed or replaced. A
replacement element which is taller than standard may not be
used to hold the air cleaner cover open. No other components
of the air induction system may be removed, replaced or modified.
B. Engines may be rebored to the manufacturer’s first standard
overbore, not to exceed 0.020". Sleeving is allowed to repair to
the standard bore. Only OE-type standard or first overbore
pistons of the same configuration and of the same or greater
weights are permitted. No interchange between cast and forged
pistons is allowed.
C. Rotating and reciprocating parts may not be balanced.
D. Port matching is not allowed.
E. Any part of the exhaust system beyond (downstream from) the
header/manifold or catalytic converter, if so equipped, may be
substituted provided the system meets the requirements of 3.5.
Stainless steel heat exchangers are permitted only if the physical
dimensions and configuration remain unchanged. Modifications
of any type, including additions to or removal of, the catalytic
converters, thermal reactors, or any other pollution control
devices in the exhaust system are not allowed and the system
must be operable. Replacement catalytic converters must be OE
if the vehicle has not exceeded the five-year/50,000 mile warranty
period as mandated by the EPA. Converters must be of the
same type and size and used in the same location as the original
equipment converter(s). This does not allow for a high performance
unit. If the vehicle has exceeded the five-year/50,000 mile
warranty period, replacement catalytic converters must be OEtype
as per Section 13.
F. Any oil filter may be added if not originally equipped. Canistertype
oil filters may be replaced with a spin-on type filter using a
minimum amount of hardware and connecting lines.
G. The installation of water expansion tanks is allowed. The installation
of oil catch tanks is allowed provided the PCV system is
H. A scattershield may be added. This does not permit bell housing
I. Thermostats may be added or substituted. A thermostat is a
device which controls the passage of water.
J. Silicone replacement hoses are permitted as alternate components,
provided they meet the requirements of Section 13.0 with
regard to size, shape, location, and performance equivalence.
Replacement induction system air intake hoses must also match
the standard part in stiffness, contour, and internal wall texture.
K. A device for locking out reverse gear may be used.
L. Limited-slip differential, transmission and differential ratios,
clutch mechanisms and carburetion, fuel injection or supercharger
induction systems must be standard as herein defined.
M. Any oil or grease, including synthetic, is permitted.
N. Valve seats and guides in older engines originally designed for
leaded fuel may be only substituted with alternate components if
the dimensions are the same as those of the standard components.
STREET TOURING CATEGORY
The Street Touring category of vehicle modifications is meant to fit
between the current Stock and Street Prepared categories. This
category provides a natural competition outlet for auto enthusiasts
using affordable sports sedans equipped with common suspension,
engine, and appearance modifications which are fully legal and
compatible with street use anywhere in the country. “Dress-up”
items such as chrome dipsticks and non-standard filler caps are
permitted, provided they serve no other purpose.
Vehicles eligible for this category must meet the Stock category
eligibility requirements, and include all coupes/sedans with a minimum
of four seats and four seat belts, that are non-sports car based
with a maximum engine displacement of 3.1 liters, are normally
aspirated; and the small-displacement turbocharged sedans referenced
in Appendix A. No limited slip differentials are permitted
except for factory standard viscous coupler type units.
A sports car based vehicle would include those that are 2+2 variants
of 2 seat sports cars. As a guideline, eligible cars would typically
come from the D, F, G or H-Stock classes. Note that 3.2 ‘VEHICLE
CLASSIFICATION’, also applies to the Street Touring Category,
including adding or removing cars from the exclusion lists.
Vehicle eligibility lists are now in Appendix A.
Under the provisions of Section 1.1 of these rules, Regions are free
to allow the previously-listed STR class or any other version of the
ST concept which meets their local needs.
If these rules contain errors, oversights, or omissions, the Solo
Events Board and the National Office will make the necessary
corrections through the use of Technical Bulletins in SportsCar
magazine at the earliest possible date.
See Sections 3.8 and 8.3 for documentation requirements.
14.1 AUTHORIZED MODIFICATIONS - STS
A. All Solo Rules Stock Category allowances, plus all allowances
contained in 14.1 through 14.10.
B. Air conditioning systems may be removed in whole or in part.
This rule should not be interpreted to allow modification of the
14.2. BODY WORK
A. Pedal kits and other interior cosmetic accessories may be added.
B. The driver and front passenger seats may be replaced, with the
following restrictions: The seating surface must be fully upholstered:
The top of the seat, or an attached headrest, may not be
below the center of the driver’s head. The seat, not including
mounting hardware, must weigh at least 15 pounds.
C. Removal of factory trim (rub strips, emblems, mud flaps) is
D. Alternate steering wheels are allowed except that steering
wheels with an integral airbag may not be changed.
E. Fenders may not be cut or flared but the inside lip may be rolled
to gain additional tire clearance. Flares that are part of body kits
may be attached to the stock fenders. The intention is to permit
fitting the maximum allowable tire size. No other changes to the
stock fenders or wheel wells are permitted. Wear marks on
inside surfaces of the fender well from tire rub are permitted.
However, wear holes or slots completely through a fender well
surface (which, in effect, provide additional tire clearance) are
F. Addition of spoilers, splitters, body kits, rear wings and nonfunctional
scoops/vents is allowed. The intent of this allowance
is to accommodate commonly available appearance kits, and
replicas thereof, which have no significant aerodynamic function
at Solo speeds. Body kits are limited to bumper covers, valances,
side skirts, and fender flares. Standard parts may not be
removed except for the substitution of spoilers, rear wings,
bumper covers and valances. Rear wings must attach only aft of
the rear wheel centerline. Total surface area of all spoilers, splitters
and rear wing may not exceed 8 square feet as seen from
above (see 12.9). Substitution of rear spoilers or wings must
retain any original third brake light functionality unless otherwise
equipped. No underbody panels may be added or substituted.
The drilling of holes for the purpose of mounting these
pieces is permitted.
Tires must meet the eligibility requirements of the Stock category (excluding
13.3.F), with the following additional restrictions:
A. Tires may have widths up to and including 225.
B. Tires must have a minimum tread wear rating of 140.
C. Tire models must not appear on the following list, which may be
altered at any time by the SEB upon notification of the membership.
Pirelli P Zero Corsa
A. Any wheels up to 7.5" in width that fit over stock brakes.
14.5 SHOCK ABSORBERS
A. Shock absorber bump stops may be altered or removed.
B. Any shock absorbers may be used. Shock absorber mounting
brackets which serve no other purpose may be altered, added, or
replaced, provided that the attachment points on the body/
frame/subframe/chassis/suspension member are not altered.
This installation may incorporate an alternate upper spring
perch/seat and/or mounting block (bearing mount). The system
of attachment may be changed. The number of shock absorbers
shall be the same as Stock. No shock absorber may be capable
of adjustment while the car is in motion, unless fitted as original
equipment. MacPherson strut equipped cars may substitute
struts, and/or may use any insert. This does not allow unauthorized
changes in suspension geometry or changes in attachment
points (e.g., affecting the position of the lower ball joint or
spindle). It is intended to allow the strut length changes needed
to accommodate permitted modifications which affect ride
height and suspension travel.
A. Cross drilled and/or slotted brake rotors are permitted, same size
and type as standard.
B. Brake lines may be substituted with alternate DOT approved
flexible brake lines.
C. Air ducts may be fitted to the brakes, provided that they extend
in a forward direction only, and that no changes are made in the
body/structure for their use. They may serve no other purpose.
D. Original equipment ABS braking systems may be electrically
disabled, but may not be removed or altered in any other way.
14.7 ANTI-SWAY BARS
Substitution, addition, or removal of any anti-roll bar(s) is
permitted. Bushing material, method of attachment, and locating
points are unrestricted. Components such as anti-roll bars and strut
housings that serve dual purposes by also functioning as
suspension locators may not be modified in ways that change the
suspension geometry or steering geometry. Non-standard lateral
members which connect between the brackets for the bar are not
A. Ride height may only be altered by suspension adjustments, the
use of spacing blocks, leaf spring shackles, torsion bar levers, or
change or modification of springs or coil spring perches. This
does not allow the use of spacers that alter suspension geometry,
such as those between the hub carrier and lower suspension
arm. Springs must be of the same type as the original (coil,
leaf, torsion bar, etc.) and except as noted herein, must use the
original spring attachment points. This permits multiple springs,
as long as they use the original mount locations. Coil spring
perches originally attached to struts or shock absorber bodies
may be changed or altered, and their position may be adjustable.
Spacers are allowed above or below the spring. Suspension
bump stops may be altered or removed.
B. Suspension bushings may be replaced with bushings of any
materials (except metal) as long as they fit in the original location.
Offset bushings may be used. In a replacement bushing the
amount of metal relative to the amount of non-metallic material
may not be increased. This does not authorize a change in type
of bushing (for example ball and socket replacing a cylindrical
bushing), or use of a bushing with an angled hole whose direction
differs from that of the original bushing. If the Stock bushing
accommodated multi-axis motion via compliance of the
component material(s), the replacement bushing may not be
changed to accommodate such motion via a change in bushing
type, for example to a spherical bearing or similar component
involving internal moving parts. Pins or keys may be used to
prevent the rotation of alternate bushings, but may serve no
other purpose than that of retaining the bushing in the desired
C. The following allowances apply to strut-type suspensions. Adjustable
camber plates may be installed at the top of the strut
and the original upper mounting holes may be slotted. The
drilling of holes in order to perform the installation is permitted.
The center clearance hole may not be modified. Any type of
bearing or bushing may be used in the adjustable camber plate
attachment to the strut. The installation may incorporate an
alternate upper spring perch/seat and/or mounting block (bearing
mount). Any ride height change resulting from installation of
camber plates is allowed. Caster changes resulting from the use
of camber plates are permitted.
D. Differential mount bushings may be replaced, but must attach in
the factory location(s) without additional modification or
changes. Differential position may not be changed. The amount
of metal in a replacement bushing may not be increased relative
to the amount of metal found in a standard bushing for the
particular application. Solid metal bushings are specifically
E. Transmission mounts may be replaced, but must attach in the
factory location(s) without additional modification or changes.
Transmission position may not be changed. The amount of
metal in a replacement mount may not be increased relative to
the amount of metal found in a standard mount for the particular
application. Solid metal mounts are specifically prohibited.
F. Steering rack bushings may be replaced, but must attach in the
factory location(s) without additional modification or changes.
Steering rack position may not be changed. The amount of
metal in a replacement bushing may not be increased relative to
the amount of metal found in a standard bushing for the particular
application. Solid metal bushings are specifically prohibited.
This does NOT allow shimming or otherwise relocating the
G. Camber bolts may be installed providing these parts use the
original, unmodified mounting points and meet the restrictions
specified in 14.5.B. Caster changes resulting from the use of
camber bolts are permitted.
H. Live axle suspension allowances:
1. Addition or replacement of suspension stabilizers (linkage
connecting the axle housing or DeDion to the chassis, which
controls lateral suspension location) is permitted.
2. Traction bars or torque arms may be added or replaced.
3. A Panhard rod may be added or replaced.
4. The upper arm(s) may be removed, replaced, or modified,
and the upper pickup points on the rear axle housing may be
5. The lower arms may not be altered, except as permitted
under 14.8.C, or relocated. Methods of attachment and attachment
points are unrestricted, but may serve no other
purpose (e.g. chassis stiffening). This does not authorize
removal of a welded-on part of a subframe to accommodate
I. Camber kits, also known as camber compensators, may be
installed. These kits consist of either adjustable length arms or
arm mounts that provide a lateral adjustment to the effective
length of a control arm. Alignment outside the factory specifications
is allowed. The following restrictions apply:
1. On double/unequal arm (e.g. wishbone, multi-link) suspensions,
only the upper arms OR lower arms may be modified
or replaced, but not both. Non-integral longitudinal arms that
primarily control fore/aft wheel movement (e.g. trailing
arm(s) or link(s) of a multi-link suspension) may not be replaced,
changed, or modified.
2. On arm-and-strut (MacPherson/Chapman) suspensions, the
lower arms may be modified/replaced OR other methods of
camber adjustment as allowed by paragraphs 14.8.B, C, or G
may be used, but not both.
3. On swing or trailing arm suspensions, the main arms may not
be modified or replaced, but lateral locating links/arms may
be modified or replaced.
4. The replacement arms or mounts must attach to the original
standard mounting points. All bushings must meet the requirements
of 14.8.B. Intermediate mounting points (e.g.
shock/spring mounts) may not be moved or relocated on the
arm, except as incidental to the camber adjustment. The
knuckle/bearing housing/spindle assembly cannot be modified
Note: Many modern suspension designs known by other names,
actually function as double A-arm designs. These include the
rear suspensions on 88+ Honda Civic/Integra, Neon, E36
BMW, and most “multi-link” and are covered by 14.8.I.1.
J. Changes in alignment parameters that result directly from the
use of the allowed components are permitted. For example, the
dimensional changes resulting from the use of a cylindrical
offset bushing that meets the restrictions of 14.8.B are allowed,
including those resulting from a change in the pivoting action to:
(1) about the mounting bolt, or
(2) about the bushing itself.
K. Subframe mount bushings may be replaced, but must attach in
the factory location(s) without additional modification or
changes. Subframe position may not be changed. The amount
of metal in a replacement bushing may not be increased relative
to the amount of metal found in a standard bushing for the
particular application. Solid metal bushings are specifically
L. Strut bars are permitted with all types of suspension. Strut bars
may be mounted only transversely across the car from upper
right to upper left suspension mounting point and from lower
right to lower left suspension mounting point. No other configuration
is permitted. Additional holes may be drilled for mounting
bolts. Only bolt-on attachment is permitted. Interior trim panels
may be modified to allow installation of strut bars. Holes or
slots may be no larger than necessary and may serve no other
purpose. This does not permit any modifications to the frame or
unibody beyond the allowed mounting holes.
14.9 ELECTRICAL SYSTEM
The make, model number, and size of the battery may be changed
but not its voltage. Relocation of the battery or batteries is
permitted but not into the passenger compartment. If the battery is
relocated and the original battery tray can be removed by simply
unbolting it, the tray may be removed, or relocated with the battery.
Holes may be drilled for mounting or passage of cables. Longer
cables may be substituted to permit relocation. The number of
battery or batteries may not be changed from stock. The area
behind the rearmost seat is not considered to be within the
Engine and transmission must remain unmodified, including emissions
equipment, except as noted below:
A. Internal baffling of oil pans may be added or modified. Addition
or modification of windage trays, crankshaft scrapers, and oil
pump pickups is not allowed.
B. Original equipment traction control systems may be electrically
disabled, but not removed or altered in any other way.
C. The air intake system up to, but not including, the engine inlet
may be modified or replaced. The engine inlet is the throttle
body, carburetor, compressor inlet, or intake manifold, whichever
comes first. The existing structure of the car may not be
modified for the passage of ducting from the air cleaner to the
engine inlet. Holes may be drilled for mounting. Emissions or
engine management components in the air intake system, such
as a PCV valve, or mass airflow sensor, may not be removed,
modified, or replaced, and must retain their original function
along the flow path.
D. Exhaust manifolds and headers may be replaced with alternate
units which are emissions-legal. Relocation of the oxygen sensor
on the header is permitted. Alternate oxygen sensors, including
heated types, are permitted. This allowance does not
permit relocation of the catalytic converter (see 13.10.E). Exhaust
heat shields may be modified the minimum amount necessary
to accommodate allowed alternate exhaust components.
E. The engine management system parameters and operation may
be modified only via the methods listed below. Any and all
modifications must meet or exceed the applicable US DOT emissions
standards for the year, make, and model of the car. These
allowances also apply to forced induction cars, except that no
changes to standard boost levels, intercoolers, or boost controls
are permitted. Boost changes indirectly resulting from allowed
modifications are permissible, but directly altering or modifying
the boost or turbo controls, either mechanically or electronically,
is strictly prohibited.
1. Reprogrammed ECU may be used in the standard housing.
Traction control parameters may not be altered. Altered
engine controllers may not alter boost levels in forced induction
2. Electronic components may be installed in-line between an
engine’s sensors and ECU. These components may alter the
signal coming from the sensor in order to affect the ECU’s
operation of engine management system. Example: fuel
controllers that modify the signal coming from an airflow
3. Fuel pressure regulators may be replaced in lieu of electronic
alterations to the fuel system. It is not permitted to electronically
modify the fuel system AND replace a fuel pressure
4. Ignition timing may be set at any point on factory adjustable
distributor ignition systems.
5. VTEC controllers and other devices may be used which alter
the timing of factory standard electronic variable valve timing
6. All STS vehicles must comply with the Federal 49-state safety
and tailpipe emissions test requirements as a minimum.
F. Any mechanical shift linkage may be used.
G. Any accessory pulleys and belts of the same type (e.g., V-belt,
serpentine) as standard may be used. This allowance applies to
accessory pulleys only (e.g., alternator, water pump, power
steering pump, and crankshaft drive pulleys). It does not allow
replacement, modification, or substitution of pulleys, cogs,
gears, or belts which are part of cam, layshaft, or ignition drive
or timing systems, etc. Any crankshaft damper or pulley may be
used. SFI-rated dampers are recommended. Supercharged cars
may not change the effective diameter of any pulley which
drives the supercharger.
H. Engine mounts may be replaced, but must attach in the factory
location(s) without additional modification or changes. Engine
position may not be changed. The volume of metal in a replacement
mount may not be increased relative to the volume of
metal found in a stock mount for the particular application. Solid
metal mounts are specifically prohibited. Any non-metallic inserts
may be used.
Hydraulic shock type rear engine locators, or bobble struts may
be replaced by manufacturer’s performance part, or aftermarket
replacement part. This part must retain factory dimensions and
attachment points, including factory design. (Example: If factory
locator/bobble strut is gas or hydraulic piston type, replacement
part must be gas or hydraulic piston type. No solid mounts may
Sources…. www.Sfrscca.com, www.scca.com, SCCA rule book, Auto Cross FAQ’s by John Crooke, www.sff.net.