is it just to put gear on D and hit the floor? then you can adjust stereos and enjoy slow-motion scenery or is it better to shift manually? what shift points you are using?

-P (just asking)

 

In drive...power brake to 1200-1400 dump it....provided the posi is good and you have decent tires it should hook.

 

I always shift manually. If the motor is stock, take it to 5000, depending on your mods, you can go higher. I shift at 5500 or sometimes even 5750 on a cool night.

------------------
1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Accel High Flow TPI Baseplate, Edelbrock TES 1 5/8" Headers, Catco 3" High-Flow Catalytic Converter, Hooker 3" Aerochamber Cat-Back System, Transgo Shift Kit, Performance Resource Chip, Accel Ignition, K&N Filters, Jet TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET: 14.32 @ 97.7mph
(corrected for elevation)

 

I agree....

adding to it, I would launch at 12-1300RPM and feather it out of the hole, just enough so you hear the tires slightly chirping as your accelerating.

OH...and put a high-stall converter on the top of your mods list.



------------------
Mike L.

The Weapon of Choice:
1987 IROC Z 5.7 TPI A4 3.27 Borg-Warner four wheel disc
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog, few others I forgot...???

**BOYCOTT LAPEER DRAGWAY**

 

Iroc5.7: what times/mph are you running? I know you said that you were running almost as fast as I am, so I am interested in knowing how much of that is in the stall. Once I get a Spohn torque arm (stock one broken) and good tires, I expect a 2300-2500 stall to get me into the 13.50s on a cool night. How much of an improvement did you notice before and after the stall?

Thanks
Kyle

------------------
1990 Firebird Formula 350 speed density TPI; Edelbrock HI-FLO base and Runners w/portmached plenum; air foil; Comp Cams 1.6rr; Edelbrock 1&5/8" headers; MSD 6AL, HEI coil & plug wires; underdrive pullies; Hypertech stage II chip; AFPR; B&M stage II shift kit; 3.73:1 rear; Jamex 1.5" lowering coils; Spohn subframe connectors, LCA's, and LCA relocation brackets; free mods; !cats; !Smog Pump; PLUS...1300w stereo weighing 200 lbs.

 

Before these mods:
Ported intake, Y-pipe, int. pipe, 160* stat, and MSD 6A, the fastest I went was 14.0 at 98MPH. The car went 14.5x at 93mph stock with no mods. The first mod I made was the converter/trans work. I went 14.2x at 96mph.
After all the free mods I went into the 14.0's. Now I've added the above, and hope to be in the 13.80's if I'm lucky.


------------------
Mike L.

The Weapon of Choice:
1987 IROC Z 5.7 TPI A4 3.27 Borg-Warner four wheel disc
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog, few others I forgot...???

**BOYCOTT LAPEER DRAGWAY**

 

I let the tranny do it and it shifts at about 4600-4700. It seems like that is the best place to do it because up top it doesn't pull nearly as hard. Remember these are high tq motors, not high hp. Staying in the middle of the powerband will get you moving the best. If you have some mods that allow better breathing I would pull it to 5000 or a little more maybe, but not stock.

Just my $.02

 

I agree with shifting earlier to, it has been proven by road trest that stock TPIs run better 1/4 mile times and 0-60 times when shifted in the 4200-4500 rpm range. Now this will change with those who have done work in the plenum, runners or a cam/head swap.
Though since the question was "stock" L98 here is what to do. Trial and error to find the best way to launch with just a slight squeel to the tires holding the throttle down as close to the floor as possible until you feel full traction and mash it. Let the tranny do the shifting and adjust the Kick down cable to a point where it is shifting at peak HP, which is around 4200-4500 rpm.
Does it matter if your in D or OD, NO the tranny doesnt know the difference at WOT.
Shifting manually only holsd the shifts past where the Auto wants to shift at and when you put the shifter into the next position you are then just allowing the Tranny to shift which hurts you in the fact that everyone knows you cant outshift an automatic.

------------------
89 Trans Am Turbo 3.8L All stock 43,000 miles #1053 of 1555

Past Thirdgen:
86 Trans Am w/ built 355TPI with SLP goodies and too much other stuff to List. One sweet *** car, wish I would have had a good enough Job to pay insurance on three cars so I could keep it, but for a 89 Turbo Trans Am w/ Low miles, I think I made the right choice!

 

Try and keep it cool. The cooler they are the better they run. So far i only been able to go to the track when it is 90 degrees and humid. But times vary from 15.0 to 15.8 depending on how hot the engine is. My carbed performance cars never varied that much.

 

I have a 1992Z with the L98 that is stock except for the K&N filters and Borla muffler.I have serious loss of traction in 1st and 2nd gear.I have Bridgestone Potenza 245-50-ZR16 tires.What is the best street tire for better traction? I will be buying new tires in a few months. THANKS

 

I just purchased BFGoodrich g-Force T/A's and they seem to work quite well for traction. Plus you get a free g-Tech Pro.



------------------
Brett

'91 Z28 Black
125K,L98,3.23,4L60.
Panhard,LCAs.
-------------------------
MN F-Body
Brett's House

 

Finally learned how to adjust the transmission kickdown cable. Now it shifts 1st to 2nd at 4000rpm and 2nd to 3rd ar 4400rpm which is much better than waiting all day for it to reach 5000rpm to shift. I'm expecting 14.70's next trip to the track.

 

I put the ol' girl in drive, hold the brake in, step on the pedal and tach it up to about 1 grand give or take, then romp down on the pedal like nobodies business when the tree turns green. I spin a little, but then I'm running on some 245-50 R16 Generals, the good part is that I'm running 14.3 and 14.4s consistantly

------------------
j.wolfe
_ ____ _
91 GTA L98
Best time: 14.389@95.49 (VMP)
"...Deception..." Brandon Sloan * ...wounds heal and chics dig scars...

 

actually the one i've, is modded with 0$

i've ported the plenum, gutted the cat, timing at 12 deg, accel air filter, removed fogs, MAF screens removed and cold air by rotating air filter housing also rest is on my signature... i bet with those mods effect is more likely +/-

but so far i haven't accelerate from 0 to 60 under 7 seconds

next will be removing knock sensor with right resistor.


-P the owner of slow GTA


------------------
Pontiac Trans Am GTA'89

CC1 GW6 G80 JG1 L98 MXO N64 WS6 822

mods: firebird '89 four spoke steering wheel and i'm still not running low 13's yet!

 

My reaction times are much better when I launch from idle. Power braking might have got me an extra 1/10 second but I'd give it up with ****ty reaction times.
I don't think tpi cars with long tube runners need any power braking and have plenty of power right from idle.
Keep in drive for better consistancy and make sure 2-3 shift happens before 5,000 rpm. Covette server will help the tranny shift a little quicker.
The setup that has worked best for me is deep staging and romp on the gas right when the last yellow comes on. Have several .001 reaction times this way, still have not had a .000 (would be .500 if your track does not use a "zero" clock)