noboostnogo

iTrader: (4)

im having massive problems launching my 6 spd trans am. 3.73, stock clutch, posi, adjustable torque arm and 275 50 r15 mickey thompsons DR and if i launch at anything under 4k rpms the tires will stick and engine will bog down a bit then pick up. 2.0 60ft, higher than 4k it spins like crazy, and if i try to control the clutch no spin, no bogs but 2.0 60ft

with my old 700r4 i was gettin 1.7xxx

what do you guys do?? any tips??

5678TA

since stick cars dont have a converter to hold the rpm in one spot, you need to launch at a higher rpm and predict the bog down to the peak torque of your motor.

DR's on the other hand are basically a hit or miss tire. thats why they work so well with auto's.. sticks shock them too hard so it breaks the adhesion and its over.. you need bias ply tires because they can handle the shock so it will allow you to launch higher and they are more forgiving to spin.

or more gear to control the bog but you still need a tire that will handle the higher launch.

noboostnogo

iTrader: (4)

interesting, bias ply tires??? is that what they are called?? never heard of them before but i am def. looking forward to trying them.

1MeanZ

iTrader: (9)

By saying bias plies he means for you to use a real set of drag slicks that are not DOT legal. Like M&H Racemasters, MT ET Drags, etc.

DIGGLER

iTrader: (1)

the '94-'02 f-body t56 trans has a lame 1st gear ratio which makes it tend to either bog or spin. i dumped my clutch around 6200 with 4.30 gears in a 12 bolt. spun the tires over 2-3 times and got mid 1.5 60's with 26x11.5x16 et streets on stock wheels.

noboostnogo

iTrader: (4)

lol

<---- noob

noboostnogo

iTrader: (4)

thats nice, when i tried doing that i spun the whole 60ft kinda. then chirped into 2nd too.

ZONES89RS

iTrader: (2)

Did you play with the tire pressure? If you had 30lbs in the back, that is one reason it spun.

5678TA

bias ply is basically any kind of slick type tire that is not a radial.

i ran the same tires you have and they did not like anything over 2k rpm. but somehow it would consistently do 1.8x 60ft's spinning near all of first. but i was running drag front suspension so the weight would stay on the rear longer.

i ran between 10 and 12psi on the DR's and thats what worked best for me. now i'm on a 28x11.50-15 Hoosier QTP at 14psi. and still having problems as you can tell by my sig. best of 1.65 and second best at 1.69..

Jay

iTrader: (2)

Best I have gotten is a 1.86 60FT. that was at 18 psi. and about 1800 RPM
Next run I tried 2500 and spun again.
T56 and 4.10 gears. Stock TPI 350.
I decided to take the easy way out and make my 87 RS with the automatic the "race" car.

noboostnogo

iTrader: (4)

yeah i started with my psi at 25 and dropped it down 2 psi at the time till i got to 14. My best results were at 22-23 when i got a 1.9xx 60ft.

So you are sayin that even with some straight up slicks you were still spinning?? that doesnt give me much hope, lol, but the 1.65 is def nice. ill be happy with what i was gettin with the auto 1.7xx


i miss my 3200 stall converter

5678TA

i think it was just the tires. i noticed that other race cars had rocks stuck to their tires after a run and they were the ones that were hooking hard. my tires have never picked up anything other than dust. and when they did pick things up, thats when i got my 1.6x's..

just do a nice burnout and they will be fine. but trust me when i say that you should not let one person's problems bring your hopes down. many and i mean many people have had GREAT luck with slicks.. i just happen to be an unlucky one..

ZONES89RS

iTrader: (2)

True, my 89 with a 5 speed and ET streets would dead hook at a 5500 RPM clutch dump, but the 2.73 gear made a 2.0 60 foot, so you should be getting WAY better than that, with my T5 on a stock motor and 4.10s i was getting 1.8s babying it(trying not to break the 4.10s).

89ROC-Z

iTrader: (7)

SO with non dot legal slicks you guys are just dumping the clutch around 5500?

5678TA

i would say that DOT slicks have just a hair less traction than a non-DOT..

i would not just go dumping the clutch on a stock rearend with a slick.. DOT or not.. its very hard on parts and the rearend is probably the weakest part of our cars..

but if you must try, the norm is anywhere from 4000 to 6000rpm.. and be prepared to spend $$$ on a replacement rearend.. might as well get a 12 bolt or 9" after the first one breaks.. if the 3rd gen is your only ride, set aside some money so you can fix it if it breaks before you go on your mission of destruction..

candle

yeah, this guy's right. the first thing to go when anyone buy's slick is the rear end, you end up with broken axles, broken axles can mess up your rear end housing, and now you're replacing a lot. lots of money

noboostnogo

iTrader: (4)

my MT DRs still have some thread left so i will do a nice burnout next time. If i break my 10 bolt i guess i will have to spend the money ive been saving up for the afr's on a 12 bolt. This is just my weekend/strip car not my DD.

ejmcdona

Don't dump the clutch ...its really hard on parts ....feather it out an launch around 1500-2000 rpm

my bone stock t-5 equiped 305 got a 2.2 on street tires (245-50-R16)

1320_Guy

iTrader: (3)

I got a best of a 2.1 60 with my stock pegleg firebird. I would rev it up to about 4000 then feather the clutch out. It took a few runs to get used to it but it works when your having traction problems.

Shagwell

Lots of kinda of "off" advice in here.


While sticks and drag radials don't co-operate well, with the proper tunning it can be done. No tire truely "dead hooks", as there is no rubber that has a perfect co-efficient of friction. Radials slip a lot less than slicks do(almost none), but it is still somewhat a "controlled spin".

My street car went 1.66 60fts, averaging between 1.66 and 1.69 most every pass on 315/35/17 nitto drag radials. Nittos of course not being the best drag radial either. My buddies stang went 1.69-1.71 60's on the same tire. Both with 5 speeds, both launching over 5k, my vert was a 3.73 gear with a stupid low 1st gear(4th gen v6 T5) while his stang was a 4.10 rear gear and a TKO500 2.97 1st gear. His car was actually more consistent and only did the 1.6 numbers on the 4.30 and the 4.56 gear. I would bring mine up to around 5200, then stand on it and slip my foot off the side of the clutch as the last yellow flickered. - Somehow my 10-bolt withstood a good season of this and is still very clean inside. It is "fully built" though(money I would not spend myself, got a killer deal).

That same stang is now t-trim equipped making 584rwhp on the stock pulley. It's now on 275/50/15 Mickey radials, and is cutting 1.52 60's on the base-line suspension tune, coming off a 5500rpm 2-step launch. I will get a 1.4 out of it yet as is, and then will put an anti-roll in it to see what we're leaving on the table. We've been running the tires right around 15psi, so far that has worked well. As I make suspension changes I vary the tire pressure to see how it reacts.



From my experiences with a stick and radials; pinion angle is a major key, nextly spring rate and shock valving. With the small side wall 315's I ran as much as -6 degrees in my tq arm car, we ran as much as -3.5 with the stang. When he put the 275/50/5's on, I had to back it down to around -1/2 degree; I can make a noticable difference in how the car hits initial vs how it holds 5' out by varying the angle 1/4 degree. As for shocks/springs, a stick car tends to work better with quick weight transfer. An auto car has the converter to cushion the hit and multiply torque as it comes out, thus allowing it more time to transfer the needed weight. A stick car needs that weight transfered fast, to kepp it from unloading, but at the same time, to adrupt of max stroke in the front end can also cause the tires to unload.

It's all in the tune man. Slicks are a lot more forgiving, but radials will work better if the time is spent to find the tune-up for them.

noboostnogo

iTrader: (4)

^^ thanks for all the info, now that i think about it i havent checked my pinion angle in forever, i should get under there and do so and maybe make some adjustments..

What rear shocks did you run if you dont mind me asking?

Shagwell

Oddly enough, both cars were on stock replacement rear Monroe Sensa-tracks when they were on 17's. He killed his inside of 20k miles and his 60's went to **** quick. He swapped to QA1 single adjustables, but had other issues that never got sorted out till after he went on the 15's. The stang was 90/10 fronts, and is now stange single adjustables with travel limters. My GTA was just KYB fronts.

I was running the eibach sportline rear springs with heated(lowered) WS6 fronts. The stang utilizes a 4cylinder front spring from a early/mid 70's pontiac lemans, and stock mustang 6 cylinder rears. - The stang has pulled the front tires on the street on more than one occassion.

Part of why my car worked as it did was a monsterous stereo system in the trunk. Dual rear mounted batteries, a couple competition subs weighing over 40lbs each, multiple amps, etc. His on the other hand is entirely due to playing with the suspension. We've run 3 or 4 different rate front springs and alternated the rears once or twice. The adjustable shocks were a big key, along with the limiters that keep the strange fronts alive(2 previous sets beat the pistons loose). We run the passenger's rear shock one click tighter than the drivers' shock, seems to help the stock sway bar. We run the rears tighter on the track than on the street; the fronts looser when racing/spirited driving.

candle

I was watching GM's new launch control for the new 2010 corvette's and it's pretty interesting. It's for a manual transmision and what it does is holds the RPMs at a certain level according to which engine you have. Well I was figuring if the ZR1 being supercharged, can launch great on a 6 speed, why can't our cars without supercargers?? Just a little thought though

laiky

The ZR1 has all the torque it needs way down low, so it won't bog. I don't drag race at a strip but my best results are letting the clutch out at 1100 rpm on street tires. I don't snap it, i release it fast but allow a tiny bit of slip to cusion the shock to the tires. I have found (as a street driver) that using your ankle to slow the engagement of the clutch as your lifting your leg helps enormously with control. I think your first problem is one of technique, not that tuning or parts won't get you around that.

hairysox33

iTrader: (4)

The new MSD 6Al-2 has a two step launch control... Might want to check that out.

candle

I didn't mean to put ZR1, it's for ALL corvette's with a 6-speed or 5-speed, I dont think they make the 5-speed anymore though. anyway it's for even the base LS3 corvettes. so if you use their ideas maybe we can launch our cars better

noboostnogo

iTrader: (4)

i havent heard many good things about 2 steps on our cars, i heards some bog and misfire when you floor it or something like that but idk.


is there any way we can preload the suspension like with the automatics??
i know keepin one foot on the clutch and one on both the break and gas will be really hard so has anyone tried using the e-brake??

i dont see how we can preload the suspension without some kind of hand break for the front wheels.

AHHHH i need to put my line lock onn

Jay

iTrader: (2)

Not just the Corvettes.. the HHR SS has it too

89305formula

iTrader: (5)

theres no way to preload the suspenson with out burning the clutch up, the best way to launch a clutch car is put slicks on it and launch it on the limiter, i get 1.61 60fts doing that with the cheapest clutch you can buy

Shagwell

Usually the cheaper the clutch the less aggressive it is, therefore the more "cushion" it will have at the launch.

A properly set-up two step makes it easier to focus on your clutch drop/dump technique, but you will still have to find the technique that works best for you/your car.

Auto cars with trans-brakes don't load the suspension either. Whether it's loaded or not does not matter, its just something else to be accounted for in the tune/technique.

candle

haha, yeah and it's sweet anyone seen the vid??? if not here it is, I've been tryin to launch my 91 RS with the same technique

http://www.youtube.com/watch?v=u9wRW-Ysxck