Posi Vs. Truetrac
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Posi Vs. Truetrac
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).
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).
#2
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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
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
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ATI ProCharger and Moser Sales 260 672-2076
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https://brutespeed.com/ Link to website
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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.
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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.
That diff is high bias enough for road course use, and strong enough for decent power sticky slick/DR launches/60 foots.
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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
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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
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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.
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.