gearing help
gearing help Hey guys im looking for some gearing help on my car. I have a 98 Camaro stock cubic inch ls1 346 that is a drag race only car. the current combo is stage 2 GTP heads, Fti street sweeper cam with a victor jr and 850 carb. im running a th400 with a transbrake and 5100 stall converter, 9 inch and 4.56 gear with a 28.0x9 M/t bracket pro radial tire, car weighs roughly 3200 with driver. shifting at 6800 and going through the traps around 7-7100
I have the 2 step set to 3800 if I go any higher is starts to spin. I do have front and rear coil overs strange up front and qa1 in the rear. bmr front kmember and lower control arms, rear trailing arms, extreme duty torque arm and drag race rear sway bar. The car runs good but I think im over gearing it. I feel like it should be a little quicker than what it is. Thinking of trying a 3.90 gear to see if it likes it better but looking for opinions.
current best pass with setup
60- 1.509
4.454
1/8 6.931
98.50 mph
1000 9.086
1/4 10.910
123.26 mph
I have the 2 step set to 3800 if I go any higher is starts to spin. I do have front and rear coil overs strange up front and qa1 in the rear. bmr front kmember and lower control arms, rear trailing arms, extreme duty torque arm and drag race rear sway bar. The car runs good but I think im over gearing it. I feel like it should be a little quicker than what it is. Thinking of trying a 3.90 gear to see if it likes it better but looking for opinions.
current best pass with setup
60- 1.509
4.454
1/8 6.931
98.50 mph
1000 9.086
1/4 10.910
123.26 mph
With a 3.90, you're going to shift (6800rpm) 1-2 at 55mph, 2-3 at 92mph and cross at about 6,200rpm. This is taking into consideration your converter slip, which is actually pretty low. Where is your power peak RPM? How far does it carry out? 3.90 is probably too low unless you're looking at adding power and a higher trap speed. 7,000rpm in 3rd with 4% slip and a 3.90 gear is about 141mph.
Not sure where the peak power is never had this motor on the dyno. I'm not looking to add any power adders to it. Not sure if it would be worth trying a 4.30 or going to a 4.10 or just stick to what I already have In it
Joined: Aug 2007
Posts: 24,241
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From: Turnin' Wrenches Infractions: 005
Sounds like its working ok now. I just swapped gearing in a similar combo/weight car and gained nothing, which tells me you probably wont gain or lose anything by making a gear swap. The reason I think that is, is because the converter is doing all the work and makes gearing much less important.
I think your right. I don't think im going to change anything. Ill wait until I build a bigger motor with some power and then see If I need to make a change. thanks for the info.
