The setup: NWF front swap using 12x1.25 rotors with Hawk HPS pads and the G-body single piston calipers. Daytona rear swap using 11.25x0.875 rotors with Hawk HPS pads. Hankook Ventus H405 all season tires. I had been driving nicely for a while, so the pads were warmed up.
So, today I decided I needed to come to a quick stop because of some douche that decided to make a left turn and the 4 cars in front of me accordian'd. I gotta say damn, the car came to a @!#$ fast stop.
Anyway, everyone knows (or at least they do now) that there is a certain point where you can actually brake faster than the coefficient of static friction can hold your rotating tire to the road. As I came to a stop from about 60, the right front tire slightly jerked, like if it was ABS giving out one pulse, not full ABS pulsing. Now, as many people on this site know, the ABS system does great for dynamic brake balancing of the car, but absolutely sucks for actually helping you in a lockup situation. The only times I can get ABS to engage is when I've hit a bump or a pothole while doing some mild braking, and the car gives the "durrrrrr" sound.
So that got me to thinking, I really love my brakes, the balance of the car is incredible, and it stops phenominally. But at the same time, I was wondering, if I actually came to the point of being able to brake faster than the tires could handle it? I know some of you are gonna call BS and say "there's no way you can do it in a cavy!" but remember, these arent Michelin pilot sports I have on my 16" wheels. It actually got me to thinking whether my quick jerk was the ABS burping "wudup" (even though it didn't sound like activated ABS, and it only chirped, meaning that it wasn't a full skid) or if it was my tires saying "ughhhhh".
Opinions from knowledgeable people?
-----------------------------------------------------------------------
-----------------------------------------------------------------------
- Sold my beloved J in April 2010 -
When I got my first set of slotted rotors, axxis ult. pads, and SS lines I was able to break traction on a set of factory RSA's from an '03 at 55mph. I can definitely see you being able to do it with your brake setup... No BS flags here.
I believe it. I locked the Wilwoods a couple days after my initial test on a 60-0 stop (I was intentionally trying to lock 'em that time). ABS stopped working after putting the Neon's on
my ABS never engages from strictly braking. ive locked them up a few times. like you said, it only works when you hit a bump or pothole.
If you can't lock up the wheels that when its time for better brakes... IMO you never want the brakes to be the limiting factor, you want the tires to be the limit.
I tend to get rear wheel ABS activation during hard braking. When I was running stock brakes and suspension, the effect was terrible. Things are much improved with better suspension keeping weight transfer in check, but it still happens. I wish I had a proportioning valve sometimes. Maybe just some grippier pads up front would help me.
Edited 1 time(s). Last edited Monday, October 08, 2007 9:56 AM
Shop Manuals, Brochures:
www.kenmcgeeautobooks.com
Darkstars wrote:If you can't lock up the wheels that when its time for better brakes... IMO you never want the brakes to be the limiting factor, you want the tires to be the limit.
Locking up the brakes isn't the key to a good stop though, if anything it is going to severely hurt your braking performance by allowing there to be less traction, which = longer stopping distances. I'm sure you probably know that though, being in auto cross and getting into performance driving.
I see where you are coming from about wanting the tires to be the limit of the braking performance, and I agree. I wish my Camaro had alot better brakes from the factory, hopefully things will change soon.
1983 Camaro Z28
ling427ttvette wrote:Darkstars wrote:If you can't lock up the wheels that when its time for better brakes... IMO you never want the brakes to be the limiting factor, you want the tires to be the limit.
Locking up the brakes isn't the key to a good stop though, if anything it is going to severely hurt your braking performance by allowing there to be less traction, which = longer stopping distances. I'm sure you probably know that though, being in auto cross and getting into performance driving.
I see where you are coming from about wanting the tires to be the limit of the braking performance, and I agree. I wish my Camaro had alot better brakes from the factory, hopefully things will change soon.
nowhere I did I say or even imply that locking up the wheels is the fastest way to stop... the best stopping is when the tires are on the edge of locking up but still moving... if your brakes aren't capable of locking up the tires you will never hit that point and if your not hitting that point there is room for improvement
i dont think you really want either to be a limiting factor. you want the tires and the brakes to compliment each other. they work together to slow you down, so whats the point of having really good brakes that lock up your tires or really good tires that you brakes arent using the full potential of?
personally, i would rather have better tires than brakes. im not saying i dont like to be able to stop, but the braking distance and controlability of the braking should be better that way. if your constantly having to worry about locking up your tires you may be hesitant, atleast at first, about how much braking force to apply.
i find that if the tires are grippier than the brakes, then you dont so much have to worry about that. you may have to brake earlier when heading into a corner, but im sure that would be easier to control and probably provide better lap times then you constantly locking the brakes up in every corner.
1997 RedR - ZedR
if your consistantly locking up the brakes in every corner you either have something wrong with you car, your running a donut spare on all 4 wheels, or you can't drive
it was an example jackass... same as you wont always have to break early if your breaks arent as powerful because in some instances your cars normal breaking power is enough or more than enough to handle the turn.
1997 RedR - ZedR
I'm a jackass for not agreeing with you?
I was under the impression that this thread was kinda a debate.... but you can go fawk your mother if your gonna get your panties in a bunch and start name calling
Its definately a huge thing.
I had my Drag Radials on which are an R Compound tire and GAWD DAMN did it stop nice.... put the 17s back and it locks em up easy. So i think it helps to have rear discs as you want your car to stay as level as possible while braking as to not load and unload the rear suspension which can lock up the rear tires or the front ones depending on the weight transfer.
my wilwoods/baer copies saved me from putting my nose up a new stang verts ass , i needed a 4/5 point harness to keep everyone in the seats , LOL
i was on 225/45/17 azeins sports the older tread , and they it to lock up , abs didnt kick tell i was closer to a dead stop and swerved to go around the stang
Darkstars wrote:I'm a jackass for not agreeing with you?
I was under the impression that this thread was kinda a debate.... but you can go fawk your mother if your gonna get your panties in a bunch and start name calling
your right. your not a jackass for not agreeing with me... the word i was more or less looking for was smart ass.
your a smart ass for making a coment like if you lock up your breaks in every corner you are a horrible driver and all that other crap. yeah your probably right on what you said about it, but i was just using it as an example. i would really hope that some one wouldnt lock them up on every corner.
regardless i still think that i would rather have my tires not be the limiting factor in a good breaking setup. generally if you are autocrossing or street coursing the car you can always use the engine to break as well by downshifting (assuming its a 5spd). if your tires are the limiting factor for breaking, then how bad are they limiting your handling?
1997 RedR - ZedR
Not sure about your problem, but I know I can'y lock up my brakes and I also can't engage ABS (thank god). I can hit my brakes as hard as I want from 60-70 MPH and ABS does not kick on. Of course it heats the hell out of my brakes after doing it from that kind of speed. I love my brake set-up the way it is.
FU Tuning
whitegoose( RedR-ZedR) wrote:Darkstars wrote:I'm a jackass for not agreeing with you?
I was under the impression that this thread was kinda a debate.... but you can go fawk your mother if your gonna get your panties in a bunch and start name calling
your right. your not a jackass for not agreeing with me... the word i was more or less looking for was smart ass.
your a smart ass for making a coment like if you lock up your breaks in every corner you are a horrible driver and all that other crap. yeah your probably right on what you said about it, but i was just using it as an example. i would really hope that some one wouldnt lock them up on every corner.
regardless i still think that i would rather have my tires not be the limiting factor in a good breaking setup. generally if you are autocrossing or street coursing the car you can always use the engine to break as well by downshifting (assuming its a 5spd). if your tires are the limiting factor for breaking, then how bad are they limiting your handling?
Lets put it this way... are you running low treadwear tires (as in less than 275 tread wear)
Do this... you already know how those tires react, now put a set of 600 treadwear tires on and try the same thing (hard rubber as in donut spare). I almost guarantee that they will lock faster than white on rice (or at least drive the ABS nuts)
then afterwards, tell me the tires are not a limiting factor
My 17s are 380 treadwear and my Drag radials are 100 :O So i can tell there is a BIG difference.
And my dick is bigger than all of yours', so everyone needs to relizzax.
Anyway, my brakes sure do work well
-----------------------------------------------------------------------
-----------------------------------------------------------------------
- Sold my beloved J in April 2010 -
whitegoose( RedR-ZedR) wrote: your a smart ass for making a coment like if you lock up your breaks in every corner you are a horrible driver and all that other crap. yeah your probably right on what you said about it, but i was just using it as an example. i would really hope that some one wouldnt lock them up on every corner.
regardless i still think that i would rather have my tires not be the limiting factor in a good breaking setup. generally if you are autocrossing or street coursing the car you can always use the engine to break as well by downshifting (assuming its a 5spd). if your tires are the limiting factor for breaking, then how bad are they limiting your handling?
In other words your example isn't really relavent?
I didn't say buy crap tires so they don't grip. I run 235/40/17 Azenis and I can still lock them up with the Wilwoods.... I guess I'm limiting my handling by not running R-Compound race tires? They are far superior tires to prolly 90+% of street tires out there.
Its like when the cavis throw 20" rims on there ad leave stock brakes... you can stomp the pedal through the floor and it wont come anywhere near locking up the brakes, it wont stop worth @!#$ either becasue if your not on the verge of lock up your not geting the most out of what have...
you don't have to agree with me, as to what stops better its not a matter of opinion its fact, as to what you prefer thats strictly opinion, I don't why you get so upset becasue mine and yours are different
ok, the reason why you can lock up going strait is becouse the abs computer divvies up break pressure based on the individual speed of every tire. when you are going strait all tires are going the same speed and if you slam on the breaks and lock all 4 up at once the abs computer will just think(ok, all wheels are at zero therefore I have stopped already" therefore it does not have reason to activate. when you are going over bumps or through a turn or over ice it is much easier for one wheel to be going faster than the other 3 therefore you abs will "realize" that it needs to kick on when you slam on the breaks.
and imo, most people use WAAAYYYYY bigger breaks than they will ever need even in autocrossing. and the aftermarket is doing nothing but profiting over it. before you beef up your breaks you should really beef up your tires becouse no matter how much force you apply your tires will only give you X amount of traction.
plus with newer cars the abs is programmed much more precisely and assumes a certain amount of break power. I have actually seen side by side break tests where aftermarket brakes actually hurt stopping distance becouse the increased braking power actually confused the abs computer. not to mention that becouse they incresed braking power without increasing traction they made the car more prone to lockup.
that being said there are many brake upgrades that do work well and heavy autocrossers should upgrade. but putting 13' rotors and 6 pot calipers on a freaking 2800lb car like alot of people do is just plain retarted and will harm many aspects of that cars preformace outside of breaking alone.
*dons flame suit and seeks shelter*
------------------------------------------------------------------
------------------------------------------------------------------
Those so naive, so hard headed, so narcissistic, that think that buy their own efforts can single handedly change the world, are always the ones that do.
Viper98912 wrote:
Anyway, everyone knows (or at least they do now) that there is a certain point where you can actually brake faster than the coefficient of static friction can hold your rotating tire to the road. As I came to a stop from about 60, the right front tire slightly jerked, like if it was ABS giving out one pulse, not full ABS pulsing.
Either you were on uneven road or have to much brake biase to that wheel.
Quote:
Now, as many people on this site know, the ABS system does great for dynamic brake balancing of the car, but absolutely sucks for actually helping you in a lockup situation.
Negative.
Quote:
The only times I can get ABS to engage is when I've hit a bump or a pothole while doing some mild braking, and the car gives the "durrrrrr" sound.
That is normal. That's because while applying your brakes and hitting a bump the brakes clamped the disc while the suspension doing the rebound and your contact patch's weight was not on the ground.
Quote:
It actually got me to thinking whether my quick jerk was the ABS burping "wudup" (even though it didn't sound like activated ABS, and it only chirped, meaning that it wasn't a full skid) or if it was my tires saying "ughhhhh".
Same as above. You have to understand that ABS works individually and it is ONLY triggered when your sensor sees the gear not moving and then realease and applies the brake so it won't lock that wheel. So in this instance, your "quick jerk" caused a transitional weight to go one side of the car and leaving the other not having sufficient weight on the contact patch in order not to triggger the ABS on that wheel.
Either you have to much brake bias or you will really need to upgrade your suspension component especially the most important suspension piece: Tires. A nasty habbit of people is to cheapen out of tires.
>>>For Sale? Clicky!<<<
-----The orginal Mr.Goodwrench on the JBO since 11/99-----
NUTCASE . wrote:that being said there are many brake upgrades that do work well and heavy autocrossers should upgrade. but putting 13' rotors and 6 pot calipers on a freaking 2800lb car like alot of people do is just plain retarted and will harm many aspects of that cars preformace outside of breaking alone.
hey man, there's nothing wrong behind putting a 14" carbon rotor behind a 8 piston brembo caliper on my cavy.
-----------------------------------------------------------------------
-----------------------------------------------------------------------
- Sold my beloved J in April 2010 -
Mr.Goodwrench-G.T. wrote:Viper98912 wrote:
Anyway, everyone knows (or at least they do now) that there is a certain point where you can actually brake faster than the coefficient of static friction can hold your rotating tire to the road. As I came to a stop from about 60, the right front tire slightly jerked, like if it was ABS giving out one pulse, not full ABS pulsing.
Either you were on uneven road or have to much brake biase to that wheel.
The road was completely flat. As for the bias, there isn't much I can do about that anymore as it should be symmetrical with the other side. Any other issues should be taken care of by the ABS module.
Mr.Goodwrench-G.T. wrote:Viper98912 wrote:
Now, as many people on this site know, the ABS system does great for dynamic brake balancing of the car, but absolutely sucks for actually helping you in a lockup situation.
Negative.
Positive. I've proved it time and time again in the past 6 years.
Mr.Goodwrench-G.T. wrote:Viper98912 wrote:
The only times I can get ABS to engage is when I've hit a bump or a pothole while doing some mild braking, and the car gives the "durrrrrr" sound.
That is normal. That's because while applying your brakes and hitting a bump the brakes clamped the disc while the suspension doing the rebound and your contact patch's weight was not on the ground.
It is not normal when you are able to lock up your brakes at other times without potholes or other uneven changes in road conditions.
Mr.Goodwrench-G.T. wrote:Viper98912 wrote:
It actually got me to thinking whether my quick jerk was the ABS burping "wudup" (even though it didn't sound like activated ABS, and it only chirped, meaning that it wasn't a full skid) or if it was my tires saying "ughhhhh".
Same as above. You have to understand that ABS works individually and it is ONLY triggered when your sensor sees the gear not moving and then realease and applies the brake so it won't lock that wheel. So in this instance, your "quick jerk" caused a transitional weight to go one side of the car and leaving the other not having sufficient weight on the contact patch in order not to triggger the ABS on that wheel.
As I said, the sound was not an ABS-related sound. I was just giving it the benefit of the doubt that it might have been ABS.
Mr.Goodwrench-G.T. wrote:
Either you have to much brake bias or you will really need to upgrade your suspension component especially the most important suspension piece: Tires. A nasty habbit of people is to cheapen out of tires.
My tire selection was never a debate in this topic, even though everyone has thrown a @!#$fit to talk about it. It is obvious that brakes > tires, which is the whole reason I started this thread.
-----------------------------------------------------------------------
-----------------------------------------------------------------------
- Sold my beloved J in April 2010 -
All mechanically sound cars can lock their tires. Its called skidding by most people or "breaking the coefficient of friction of the tires" by others who want to sound more intelligent than they are to beef up a lame idea.
If there was any possibility that cars couldn't skid ABS would never have been invented.
Contrary to the overly popular misconception, you cannot stop faster than the ABS can stop you on a car with properly operating ABS. Maximum stopping power is at the exact point ABS kicks in. Anything less than full on ABS braking is slower braking. I have tested this thoroughly with accelerometers myself, I am not parroting someone else's opinion.
Post your test data from the last 6 yrs and then I'll post mine.
sig not found
