LeadFarmer

So the time has come for a 12 bolt. I made one pass with the POS 10 bolt on drag radials and heard a loud *** pop, so that was enough for me, last thing I want is to tow this thing home.

Due to the fact that I do DD the car a little, plan to use it on road racing courses, and use it on the strip I've decided I should stick with a LSD and stay away from a locker/spool unit.

So I have 2 questions. 1: should I go with a posi or truetrac? I know the basic structural difference between the two (Posi uses clutch packs. Truetrac uses worm gears). From what I understand the Truetrac is more reliable and can handle more torque, but since I'll be road racing I also need a unit that'll behave under tight cornering conditions, so in that regard, do the two units have any differences?

Question 2: are the 33 spline axles overkill? From what I understand, the formula to calculate torque rating for the axles is as follows: 1st gear ratio X Ring and Pinion Ratio X Peak Torque X .9 (drive line loss). From what I hear, the 30 spline is rated 6200 lb-ft. So if I eventually work my way up to 450 RWTQ (ambitious, I know), with 4.10s, i'll be at 4416 lb-ft. So I should be fine with the 30 spline right? I don't wanna overkill and lose power on the dyno due to going with the 33 spline if they aren't necessary. (I go to dyno events and such).

Bob@BruteSpeed

iTrader: (16)

For an M6 I would go with a nine inch. Check out this link for info. http://shop.brutespeed.com/Brute-Spe...nformation.htm

Here is the link to the complete Moser 9 inch rears that I sell. http://shop.brutespeed.com/Moser-9-a...Ends_c2632.htm Free shipping and these rears ship out just two days after the order is received. Bob

01ssreda4

iTrader: (96)

Going from a 10 bolt torsen (worm gear) to a 12 bolt TruTrac I can say the 12 bolt is a lot jerkier when applying power. Going straight or turning is smooth and predictable but that moment where you transfer lateral weight/direction under throttle from a turn to a straight feels more abrupt then the 10 bolt ever did. Of course my unit is very low mileage and may smooth out over time, but that was my first 500 mile impression. I wouldn't choose it for a road racing application, I'd choose a clutch posi.

dailydriver

I may be wrong, but I believe that there is now a Wavetrac diff for the 12 bolts, if you are convinced that is the axle you must have.

That diff is high bias enough for road course use, and strong enough for decent power sticky slick/DR launches/60 foots.

LeadFarmer

a wavetrac would be nice, but I'm not wanting to shell out that kind of cash for just a rear. The 9in was what I wanted initially, but don't they drain more hp as well? And should I go with the truetrac or the tracloc for my application? I don't know much about the later

01ssreda4

iTrader: (96)

I would choose a clutch posi such as an eaton HD or Auburn.

LeadFarmer

I'll look around for units sold with eaton's in that case. I've heard nothing but bad things about the auburn lsd

2001WS6-DJP

With a clutch posi you will always have locking issues however the better posi's are better about the one wheel wonder. A trutrac will totally eliminate the one wheel wonder

HCI2000SS

iTrader: (2)

No to steal this thread, but how much stronger is the stock 10 bolt with a Detroit Truetrack? This is what I have, and it came this way when I purchased the car

Fazz73jr

iTrader: (3)

Probably not much if any at all... both times i broke my 10 bolt it stripped the pinion teeth.

HCI2000SS

iTrader: (2)

Damn I was hoping it would help somewhat lol Thanks!

duh

iTrader: (16)

The trutrac itself is stronger than the factory diffs. Downside is the test of the parts are now weak links.

SSellers

There is a very well respected diff builder on Team Camaro that says posi for drag, truetrac for auto-x as far as which would be tops for either, not that either can't do both.

Might as well do 33 spline. I did at only 538 lb ft flywheel on my 400 SBC. There shouldn't be much loss between a 30/31 and who knows maybe one day you'll wish you had. On the other side, if you break a set Moser will upgrade you for free but I reckon the diff is on you to match.