So I went to the track on Saturday with my ecotec (CAI, cat-back, short throw, lowered) and I was ran a 15.849 @ 87.87mph (and that was my fastest time). I had a lot of wheel hop, I tried from all different rpms (2k, 2.5k, 3k) now on the last 2 runs i know i messed up because i was taking it too far into the red zone but i just wanted to see if it made much difference. But usaully I could either let 3rd gear ride out and just as i got to the line it would bounce on the rev limiter. Also when I got home i was disappointed so I checked my tires, I was sitting at 23 psi on my front left and 25 psi on the others, I should have checked that before i left but i came right from work. Now just as a little more information, I went with a full tank of gas because I wanted to see what my fastest slowest time (the fastest I can get with all the limits, full tank, full interior, etc) I think that makes sense, right?
I have a few questions:
Would it make much difference (couple tenths of a second) If i were running at 32 psi?
Also, should i have shifted into 4th before getting to the line to maybe gain a little more?
Another thing was there was a 6mph head wind, did that not help me?
Do i just suck at driving?! (after that day I think I do)
Well here are the times
First run:
R/T - .579
60' - 2.381
330 - 6.676
1/8 - 10.252
MPH - 68.22
1000 - 13.294
1/4 - 15.871
MPH - 87.37
2nd run: (the best one)
R/T - .620
60' - 2.366
330 - 6.671
1/8 - 10.236
MPH - 69.42
1000 - 13.281
1/4 - 15.849
MPH - 87.87
3rd run: (I missed 2nd gear and wheel spin)
R/T - .727
60' - 2.302
330 - -----
1/8 - 10.493
MPH - 67.97
1000 - 13.582
1/4 - 16.182
MPH - 86.18
4th run:
R/T - .495
60' - 2.603
330 - -----
1/8 - 10.530
MPH - 69.38
1000 - 13.571
1/4 - 16.146
MPH - 87.21
"Sink or Swim, Do or Die!"
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Would it make much difference (couple tenths of a second) If i were running at 32 psi?
you could go faster. you might of went to low in PSI. buy a tire pressure gauge so you can adjust and see what PSI you are running at
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Also, should i have shifted into 4th before getting to the line to maybe gain a little more?
if you had more track left, i would of shifted
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Another thing was there was a 6mph head wind, did that not help me?
no, it didnt
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Do i just suck at driving?! (after that day I think I do)
remember, practice makes perfect
Im a Xbox 360 fanboy...and damn proud of it!!
well, looking at your 60 foots, your launch is probably what's slowing you down the most. try airing the front tires down to 20 psi, and keep the rears up higher, between 35 and 40. then when launching rev up to about 3700-4000. it sounds high, but trust me..it works.
another thing, winding out the gears to almost redline will get you best times. trying shifting at about 6300. i've tried MANY different points, and the farther you let it go..the better. and..dont be silly, 2 lines of gas (or enough to get you to the nearest gas station), and take all the extra crap out of your car. haha.
with all this, you could defiantely get into the low 15s, i promise.
good luck!
i dont think u suck at driving cuz i suck at driving took me forever to run a 15.9 which is my best time so dont be to hard on urself. that tank of gas and everything else didnt help u alot either. just keep practicing
for wheel hop get yourself a set of Poly Urathane control arm bushings they helped me out alot. i launch my car around 2000-2500 shift first 2nd at redline and 3rd at 6000 then say in 4th the remainder seems to work best for me
Quote:
I have a few questions:
Would it make much difference (couple tenths of a second) If i were running at 32 psi?
Also, should i have shifted into 4th before getting to the line to maybe gain a little more?
Another thing was there was a 6mph head wind, did that not help me?
Do i just suck at driving?! (after that day I think I do)
:
Couple tenths, by raising tire pressure, not likely. might help your MPH. You stated you had wheel hop, which means no traction, so more psi will also mean even less traction.
yes you should shift into 4. If you hitting the rev limiter right before the finish line you are losing power.
Head wind yes that can affect times some.
If you are new at drag racing, probably not to great at driving.
It is amazing how many people think it is soo eay to take a car that has these mods and run a certain time, and when it does not, think something is wrong with the car. There is a lot of things to do and look for at the track. Having the tire pressures all different on the front tires can hurt. Sounds like the rear tire pressure was too low.
Practice does make perfect.
FU Tuning
^^^yup it's all about practice. look at all the ecos and z24s in the 16s. I know I was there at first.
15.574 @ 89 mph stock
I wouldn't blame the full tank of gas to much.
Gas only weights 6lb per gallon. So a full tank of gas (14 gallons) weights 84lb. Lets assume you run with 1/8 tank (10lb) will only give you a 74lb savings.
If its worth doing its worth over doing.
ONLY 74 pounds?
ok so let's just say you didn't even strip the car, just took out your spare and jack (35 pounds, y es i weighed.) and didn't fill up your tank like a silly goose before you went. 35 + 74 = 109.
109 pounds = approx. 1 tenth.
sounds good enough to me.
Inferno wrote:I wouldn't blame the full tank of gas to much.
Gas only weights 6lb per gallon. So a full tank of gas (14 gallons) weights 84lb. Lets assume you run with 1/8 tank (10lb) will only give you a 74lb savings.
Do you know what you are talking about??? Truly 74lbs is a lot in racing. Not only that, how much that 74lbs moves when you launch, and throws to the back of the car.
FU Tuning
^^^^^^^exactly.
why do you think i'm able to run 15.0, with only catback exhaust(at the time) and an intake?
i have a 1sv(pretty much the lowest cavalier model ever.)
NOT stripped, my car weighs 2490 Lbs. so that's about 2600 with me in it...
that whole 100 pounds = .1 tenth is a total farce you mean to tell me if you take out 400lbs its only going to be .4 tenths, yea right more like a whole second
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
^^^ I agree, just look at the hb civics with swapped motors, they're running like low 14's with a simple gsr swap.
15.574 @ 89 mph stock
alot lower i know of civic hatches running 12s with just a stock b18 in it, no turbo, no nitrous no internals, and they are only a few hundred pounds less which by this equation would mean they should only pick up a few tenths?, why then did they pick up seconds
I think this formula was based on v8 cars that for the most part are all 3500 and up in weight and the heavier the car to start with, on a car that weighs 4300 lbs sure you take off 100 your prob only going to get a tenth, on a lighter car the effect is much more magnified id say we get a tenth every 40-50lbs taken off
On a car like mine where its almost 2900 without driver and me im 210-220 im giving up a considerable amount of time
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
hmm, ok i see where my information was wrong. i wasn't really saying for every hundred pounds it's a tenth..but the difference between a car that weighs 2700 and 2600 with the same power etc etc...i could see how the product of this equation would increase as more weight was taken from the car...sorry if i made that sound wrong to begin with..and thanks for clearing that up for me too. haha.
BUT anyway.. i was just trying to get the point across to Inferno that having a full tank of gas and extra weight in your car..will make you slower. even though "only" 74 pounds doesn't seem like much.
With my 160lb roomatew in the car i could only cut times 5-6 tenths slower then i am now. Currently at 15.9@86mph (if anyone didnt know).
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I have an 03 Cavalier 5spd. <img src=http://registry.gmenthusiast.com/images/tinytim12333/timmy.gif> TIMMAY
lol that's even more non-sensical. so 400 lbs only means 4 hp ? yeah right. plus weight has nothing to do with horsepower.
15.574 @ 89 mph stock
There is nothing wrong with you or the car, you just need more practice, I mean look at your launches, they are god horrible.
No offense just letting you know.
Ok gas, to the lowest. Jack spare all out. Take out anything you can still keeping it the way you like it.
I wouldn't go as much as like taking the door panels cause they don't weight much but doors? Hell yes!!!! They both weigh like 150 pounds. lol jk
If you are getting wheel hop try a different approach to launching the car.
Take it higher in RPM's but slip the clutch.
Now, I don't know if it will make a difference in your car but when you are where I am at, simply transfering weight helps.
Lower the front as much as you can afford and jack up the back as much as you can and try to keep the back as STIF as possible so that when you take off it keeps the weight on the front tires and off the back.
Think about it the less weight you have int he back of the car the better for you because just like Higgins said, that is DEAD weight(the worst), that transfers the weightto the back wheels and sag the back end donw making you lose traction in the front ones.
Shift to 4th.
If you hit that rev limiter YOU WILL INSTANTLLY LOSE 2-3 MPH.
Just get used to shifting to 4th cause I have to shift to 4th 1/2 way down the track at 1/8th mile mark, but I trap 86 mph in the 1/8th that is why.
All the little things play a roll man.
when it comes to dead weight, I was always thought that 100 lbs=10hp=1mph or a .1sec.
so you have a Hatchback Civic that weighs 2100 with a B18C1 which makes 180hp, if your Cav weighs 2600 with 140 and you run 15.30 which is reasonable on a 2.0 60 foot. 40 hp will give him .4 sec and 500 lbs another .5 sec hence them running 14.30, plus a lot of them have better 60 foot times because it is much easier to yank 2100 lbs off the line with 180 motor than 2600 lbs car with a 140 hp motor.
These numbers have always worked for me.
Another thing every .1 in the 60 foot is about .1-.15 in the 1/4
So if you just get your 60 foot down to 2.0 which is .3 you should shave about .4-.5 off the end time which will get you down to 15.3-15.4
Sorry for the long ass post.
Best time:"""11.946""" @ 114.73 mph @17psi 1.83--60"
11 second daily driver!!!!
Race Related 727-561-9440
Shop of choice for your 11 second J body!
Also, built bottom end and or top end LSJ and L61's available.
13's
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Franz Rew wrote:I had a lot of wheel hop, I tried from all different rpms (2k, 2.5k, 3k)
Wheel hoop can be prevented by double clutching off the line. Also you need top shift at 5500 RPM taht is the max torque and max hp that your motor will make.
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now on the last 2 runs i know i messed up because i was taking it too far into the red zone but i just wanted to see if it made much difference.
It does in seeing how quickly the powertrain and come apart.
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But usaully I could either let 3rd gear ride out and just as i got to the line it would bounce on the rev limiter.
Do not hit the rev limiter that will cut fuel and power to your engine. 5500 is your shift point.
I have a few questions:
Quote:
Would it make much difference (couple tenths of a second) If i were running at 32 psi?
It could have.
Quote:
Also, should i have shifted into 4th before getting to the line to maybe gain a little more?
No, you want to stay in your power gears as much as possable.
Tach Out Motorsport
Http://www.team-tachout.com/
Falmouth,VA
^^^^ you will BE SLOWER if you shift at 5500. The reason you shift higher than your peak hp is because after your shift you want to be at a rpm that is closer to your power band. For exemple if you shift at 6200 you might come down to 4500, making more power than if you shift at 5500 and drop to 3700.
I made my 15.5 pass shifting at 6200-6300. Double-clutching off the line ? Do you know what you're talking about? man the guy whose trying to get better times don't listen to this Tach Out
15.574 @ 89 mph stock
Hey Tach out Motorsports, you are very shallow when it comes to J body performance or any KIND of performance.
You are misinforming people and it would be appreciated if you would stop polluting people's knowledge with garbage posts and false information.
1st you said DOUBLE CLUTCHING!!!! Stop watching Fast and the Furious, cause you obviouslly started driving when the movie came out.
WTF is double clutch, have you ever heard of synchros?
So shift at 5500 RPM ah????
Ok so we all are going to do that and by the 4th gear we will be do far from under the good power range for the next gear that we all will run 17's like your HONDA boys.
I make peak power at 6400 RPM you dumb ass.
Stock Eco about 5700 and you wanna take it another 700-800 RPM PAST that to be in the better power range for the next gear.
2nd, the power train WILL fall apart, another stupid comment.
So, you are so familiar with our factory tachs. and the fact that the red starts at 6000 rpm and you can easily take these motor to 6500, and even 7500 if we could.
3rd, you tell him NOT to hit the rev limiter, and ONE MORE TIME to shift at 5500 rpm.
4th, the tire pressure only legit thing you made so far.
5th, the guy is asking weather he should shift to 4th, and even tho in 3rd pontless post of yours you told him NOT to hit the rev limiter now you are telling him to stay in the POWER gears! Which would make him assume to stay in 3rd gear. Conflict of information.
One more thing I wanna ask you??
What TF are power gears, aren't they all??
My 3rd and 4th are the only gears I like in these cars.
Good god why are you on this web site and god help your MOTORSPORTS!!
Best time:"""11.946""" @ 114.73 mph @17psi 1.83--60"
11 second daily driver!!!!
Race Related 727-561-9440
Shop of choice for your 11 second J body!
Also, built bottom end and or top end LSJ and L61's available.
13's
----12's
----11's
----10's
i like 3rd gear thats when the car really feels like its pulling hard. 4th is ok got better since i'm pretty much done performance bolt ons.
like said abpve practice makes perfect..try messing aorund with rpm launches/ tire pressure stuff like that till u find something that fits u.
i ran a 15.6@86 with 2.48x 60ft. and i have a little bit more done. just eep working at it. and just remeber as long as i'm here ur not the only that cant drive =)
MY 2003 SUNFIRE
"A N/A ecotec is not gonna give Honda's and Mitsu's that much of a run for their
money unless their blown or bottle fed.GM is still smokin crack!"
~1QWKZ24
www.streetracing.org, 08/2001
ok i read this post before i went to import warz at GLD. i want to work on my lanch, i only got two runs in. the 1st i lanched at 3200RPMs. wheel hopped like crazy, .367 R/T 2.373 60' 15.878 1/4 88.01 mph. the second was around 4000rpms i really don't know i was to busy looking at the tree. sprun the wheels like crazy. .153 R/T 2.484 60' 15.923 1/4 87.65 mph. that is at stock psi. ECOTEC short ram, exhaust, sturt bars, lower motor mount.
I think the formula you all are looking for is the Weight to Power ratio...
Of coarse the 100 lbs/ .1 sec theory is wrong
If your car weighs around 2700 lbs with the driver in it, having the basic bolt ons, lets say with a WHP estimate of 145, your ratio would be 18.620690etc..... the lower the ratio the quicker your car accelerates.
Even if you left out the 75lbs of fuel, the ratio drops to 18.10... Giving you a .5 Wei/HP gain. I don't know what the exact formula for the actual quarter mile time would be, but a .5 gain is better than no gain.
Then if you take out the 35 lbs of spare tire and jack... you drop to 17.862 (total of 0.758690 wei/hp gain), Your car now weights 2590lbs....every pound counts in my opinion!
Why do you think the old muscle cars that are really fixed up and professional race cars have a small fuel cell? Smaller the tank, less fuel and weight it carries.
Now to sound like a bigger nerd.... the heavier your car weighs the more mass you have to move. More mass, more inertia! Less inertia, good! More, bad...
