HRHohio

Hey guys,
Looking for thoughts (good and bad) on this combo:
2.41 gear'd 10 bolt (8.5 inch) behind a TH350 w/4000 Stall pushed by a 700rwhp turbo LS motor. It's going into a 72 Camaro, street/strip.

I know that with this gear ratio, I'll only be using first 2 gears crossing the 1/4 mile. My thoughts: similar to running a Powerglide with a 3.31 rear. One shift, that's it.

Soooo, tell me all the reasons why this is bad.

Thanks!

Oh, and "why?" you ask? Because I have a 2.41 and a TH350. Not looking for suggestions on changing the setup (i.e. "you'd be better off blah blah blah... "), just thoughts on how this setup will do.

S10xGN

iTrader: (11)

Turbo cars love the added load of higher ratio gears. Not sure if the 2.41 will be too high or not though... For instance, turbo Buicks like a 26" tire, 3.42 gear and have a 2.76 low. Most of the Buick guys tend to stay in the ballpark on that combo.

murphinator

iTrader: (2)

I had a well built 455 poncho (superduty crank rods , 10 to 1 forged pistons , balanced , blueprinted ,ported & cc'ed heads etc.... /t400/256 geared car about 25 years ago and it was a beast made enough power the gearing didnt matter , dead stop or 30 mph mash it and it was a rolling smokescreen till well into 3rd gear , many pole lengths lol

my thought is if the turbo your using makes good boost quickly you will be fine if it takes time to spool you better gear it down ( up numerically) the poncho I had was likely making 400 ft lbs before 2k rpm lol

murphinator

iTrader: (2)

double post

HRHohio

Well, I'm planning on modeling this after Wicked69's setup. Has twin 70mm On3 turbos. Because of the small turbine wheel (63mm) it seems to spool up pretty fast. Was wondering about the issue with it building up too much heat with a 4000 stall.

96lt1m6

iTrader: (31)

4000 stall????? I would be thinking 2800 Max 2.76 -3.08 w/ 27" tall tires. Be.sure to have a LARGE trans cooler and I would be doing liquid to air intercooler(s) and a custom made chiller box...

reinhardt02

No input on the setup, sorry. BUT, got any pictures of the car? I love the second gens, had one for 8 years. One day I think I may get another one and drop an LS1 into it.

HRHohio

Was thinking 4000 stall to get it into powerband faster on the 2.41 rearend it already has. Was definitely planning on running a separate trans cooler (i.e. not running it through the radiator).

As for the IC, I'm just planning on a front mount air/air IC. Fill in the big opening in the front. Will be running meth/water inj.

Appreciate the feedback.

HRHohio

Car is in ROUGH shape. My friend works as a body man, so he's doing all the bodywork and paint for me at his house. He's putting in a 4th gen interior from a donor car (2000 Camaro). Another friend has the interior, redoing the seats and door panels.

Motor is done. $500 2005 Silverado 4.8L. New rings gapped to .028, new rod bearings, new cam, freshly ported heads with 2.02 intake valves, new valve springs, new pushrods, KMJ head studs, LS9 Head Gaskets, LS1 intake and TB, ECU and harness from 2001 Camaro. Local guy tuning it.

Just worried about the rest of the driveline now. Gears and trans. Wondering how the matchup will do. It's not a competition car, but I'd like it to jump off the line. Also would like to be able to drive it on road trip if needed.

93camaro_zzz

iTrader: (13)

I know you think that your setup is "Theoretically" the same as a powerglide with a 3.31 rear gear, but they are definitely not the same. Ring and pinion gears are all different when it comes to strength and friction. For example the 4.10 gears for the 10 bolt are literally weaker than the stock 3.42's and can break easier.

All I am saying is I hope those gears wouldn't break or maybe dyno alot less because of how low they are.

96lt1m6

iTrader: (31)

The 10-bolt OP is speaking of is from the 2nd Gen f-body which is more than capable of handling the power and has been under many cars running in the 9s with Mower axles and c-clip Eliminators being the only mods.
GM screwed the pooch usin the 7.5/7.625 JUNK in any car made damn bean counters!

baSICK5.0

iTrader: (3)

I know this is almost a DECADE later but did this work out? Im currently running a stock 4.8 on 7psi, built th400 with 3600 stall, 2.41 gear in stock cutlass 7.5" rear(until my 8.8 is done). The car runs 8.50 at 81 in the 1.8th lol....doesnt even climb RPM in 2nd gear after the 1-2 shift. Its like all the acceleration is in 1st gear. Im going with a 3.55 in the 8.8 with 35 spline axles and full spool.