HHTurboVert

This seems like something that would have been covered many times, but I haven't been successful with the search option.

I have a lightly moded Turbo convertible and I am looking for some techniques to use at the drag strip this weekend. My main competition is my friends 1990 AWD turbo eclipse (GSX). I figure that regardless of my efforts he is going to get a substantial lead off the line since he his car is AWD. I want to know how to minimize this lead by launching my car the best way possible. One thing to consider when answering my question is that I have stock clutch and a lightened flywheel !!! =( This makes launching the car difficult, especially considering the heavier weight of the convertible. I know my car is faster than his once we are both moving, since I can pull from his car on the freeway no problem, but I'm not sure this is going to be enough to catch him before the end of the quarter mile. What approach to launching the car do you guys suggest I take.

-Rev super high to make up for the lack of inertia due to the lightened flywheel and then feather the clutch(remember its stock) of the line?

-Find a reasonable RPM and then drop the clutch?

-rev as high as I can and just drop the clutch!!

( I have a brand new set of 225/ 45 R17 Toyo Proxy's and a LSD aslo in case this info. helps)

My last request is for your opinions on what RPM I should shift at into 2nd, 3rd and 4th(prolly wont need on 1/4mile). I know all cars are different, I just want estimates. For reference, my engine is an S4 J-spec with stock ports and a stock turbo. The rest of my mods are in my sig.

ddub

In my N/A I did 7k clutch drops/flooring after to yield the best launch. However it still wasn't good, but slipping the clutch was worse.

That being said, though, I don't think that'd be a good idea with a turbo since you have more torque. I'd say doing a 5-6k clutch slip/feathering would be your best bet. Practice before, though, because it takes a few times before you can get good at it.

xtremeskier97

I too have an 86 N/A and did the clutch drop at 7k and shifted at 8k on all gears I needed(which only turned out to be 3 plus VERY little, if any, 4). All stock. No mods.


Indeed..practice. Find an old road that isnt busy and no cops around and practice.


Oh..and another thing about the launch...I went around the water that they spray down...and then did just a little burnout to warm up the tires...thats it.

Good luck, have fun, and be safe.

HHTurboVert

I will definately be practicing prior to the race, but I want to minimize the amount of wear and tear I put on the Clutch/drive-train by getting some ideas to start with. I don't want to fry my stock clutch practicing feathering it if it's not going to get me the best results. I also don't want to just start dropping the clutch at 7K and risk blowing my tranny or rear end(Like I did with my OEM open diff.) if this isn't the best way either.

Madrx7racer

he has a turbo though.....I noticed on my Turbo that if I held the RPMs at 3800-3900 then drop the clutch as I gradually floor it yields the least amount of wheelspin. shift around 7.5K just so you can be in your powerband in second and third gear.......should be like this:

3.8K...........when the 3rd amber light lights up
drop clutch then gradually(NOT SLOWLY) floor it..........by gradually i mean DO NOT FLOOR IT RIGHT AWAY OTHER WISE YOU'll Spin too much and lose

BUZZ

push clutch in 1/4 of the way(NOT ALL THE WAY TO THE FLOOR)
shift into 2nd (should be quick!)

BUZZ

shift into 3rd (^same as above clutch in 1/4 of the way) and stay in third untill you are done.....i don't think you'll need to shift into 4th.

best advice: let some air out of the tires to grip a bit better and get some practice runs in so you know how the track grips.....i have 225/45/16's all around and i have minimal wheelspin doing what i said above....

ddub

That part all depends on the wear on the clutch (for his case since it's stock) or type of clutch if you have an aftermarket one. I've seen a brand new stock clutch needing to be pushed in almost the whole way, so it varies on how abused his is or how many miles it has, if it's new, etc.

Madrx7racer

the technique above requires practice in order to do it right.......every clutch is different ( EDIT: DAMN YOU!! YOU BEAT ME TO IT!!). I have a 6 puck, unsprung, racing clutch(VERY GRIPPY ) so you need to find the "sweetspot" so you can shift without bringing the pedal all the way down. the best way to find this sweet spot: drive in 3rd or 4th gear (use lower gear if you are trying it on surface streets) drive nomally bring the car into neutral then slowly (while moving forward) push in the clutch while trying to put it into gear...it should slip in like a ***** in an eager vagina about 1/4 of the way down.

alex144407

in first gear floor it!
at 7K
shift it without realasing the gaz
do a ''Power shift''

ddub

Yah okay, just making sure the thread starter knew not to expect it to always be 1/4 of the way, while his still might be based on wear.

Madrx7racer is right though, find the "sweet spot" and push it in that far for shifting, it'll make it a lot quicker. With my ACT clutch and extremely short throw shifter it's pretty insane how fast I can shift at the track, make it more fun and a lot quicker.

Madrx7racer

that's what i need next.....a short throw shifter......Higgi will be getting plenty of business from me in the next few months..... same thing aapplies when downshifting but it's a bit hard to revmatch, brake and only push 1/4 of the way down as you downshift.....practice practice.

HHTurboVert

I have no problems shifting very quickly (I also have a short-throw shifter).

I am more concerned about whether I should drop the clutch or feather it, and what rpm's to shift at.

I generally shift out of first at 7K, but somtimes I feel that I am past the peak horse power when I shift at 7k in 2nd and especially 3rd. I've read that the peak power on the stock engine is supposed to be around 6500rpm, does this increase as mods are installed? If not, then shoudn't I shift at 6500 in all gears?

Would shifting after peak power ever be be better than shifting at peak power? I was thinking that shifting lower might actually make me a little faster since it would put me closer to peak torque in the next gear up. What do you guys think?

Madrx7racer, I will definitely bog if I drop the clutch at 4K(tried it). This is probably because my car is heavier than yours, and because I have a 17lb flywheel. I will try it at 5K and see if it works any better.

Madrx7racer

that's fine but remember that when you shift your RPMs drop........so you want them to drop right where you have the MOST power.....u know what I mean? so when you shift at 6.5K(peak) you drop to 5K in second then you have to build up to 6.5K.....if you shift at 7-7.5K then your RPMs drop to 6 or 6.5K(peak POWER).

I say you drop the clutch at 4K RPMs and leave him behind, you might be bogging down because you do not step on it soon enough......i wish i could put it in to words a bit better....just get out there and practive....5K WILL make you spin a lot though....

remove your spare and anything else so you can to save a bit of weight.

HyperRex

Honestly? If the guy with the Eclipse has a clue, I think your best bet is to pray he breaks the transfer case because if he beats you out of the hole, he's probably gone.

ddub

Why? It all depends on if the eclipse is stock or modded. A stock AWD eclipse turbo is only a 15.2 second car in the 1/4mile, I'm way faster than that and I'm an N/A.

Madrx7racer

where is california speedway? I wanna go.......when and how much?

Damn...it's Saturday.....can't make it....****...oh well....it was too far away anyways.

DannyD

its in fontana

sikrx

you should also drop tire pressure, all tires are different i guess but usually around 20-25psi. you'll get more traction which equals better launch

1RevvinFC3S

Well, think about this for a minute- if you are having trouble with wheelspin, wouldn't leaving the spare in the back allow better traction off of the line? Or, if you were to remove the spare, at least remove equal or greater weight from the nose (i.e. battery relocation). I'm just going from what I've seen with the grass roots backyard hotrodders with a small budget. Just a suggestion, but perhaps removing weight elsewere (like midcar- forward) will net better launches than removing rear ballast.

PureSephiroth

when i launch for an autocross i put the needle right at 4,000 rpm then dump the clutch. roll onto the throttle hard when you release the clutch but don't simply jam the gas pedal to the floor. Redline it in first gear, maybe even 500 rpm past redline. Shift into 3rd before redline. maybe 6500 rpm. If you hit 4th you can shift into that gear by 6500 rpm also.

TrboRty

iTrader: (1)

If he is a decent driver and knows how to launch the awd, it doesn't matter what you do, he is going to beat you, because of the awd system getting him out of the hole much quicker then you,and he is turbo. Stock those cars make around 220hp, with only slight mods to his car he will for sure beat you. I know cuz I use to have one, and a lot of my friends drive 1g dsm's. So umm best of luck to ya!!!

1RevvinFC3S

He's turbo as well.

TrboRty

iTrader: (1)

ok well unless he's making good hp numbers,and knows how to drive he might have a chance. But that is betting his friend doesn't know how to launch and has no mods. Awd owns rear wheel drive on 60 foot times,and once they are out there, it's hard to catch up.....

ddub

My friend has had 3 AWD turbo DSM's, and I have seen him do AWD launches at the dragstrip many times. All of them, except his current one, have been modded and the best he was able to get was a low 14 (intake, full exhaust, upped boost, better clutch, etc). So I don't see why you guys think just because it has AWD it will automatically win. Those cars have the same stock 1/4 mile time as a TII even with AWD launches. It's all up to who is more modded or who is the better driver, AWD isn't the deciding factor.

ddub

And again, I am N/A and I can easily beat my friends AWD dsm right now. Of course his is stock and mine definitely isn't, but that doesn't matter. Read my previous post.

SonicRaT

iTrader: (6)

with the 14b turbo @ 15psi with most 'free' mods and exhaust, the DSM will run ~14.5. You should've saw my coworkers look when by the time he hit 2nd i had him by 4 cars in my sport, his hole shot didn't even matter.