rear end for autoX/RR
#1
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I have a 98 T/A M6 with a H/C/I Ls6 that should be putting out around mid to high 400rwhp. My rear end is pretty much shot, and I'm looking to replace it. What is a good rear end for autocross/RR application? I've heard 12bolts or 9inch rear ends are too heavy and can upset the handling for AX/RR?? I've also heard the stock 10bolt is way too weak for the HP my car is putting out and is also not worth putting money into to reinforce. Are these statements true?? I'm open to suggestions!
Thanks guys!
Thanks guys!
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i cannot find any thing that says the % of weight over the front wheels. i heard That 1998 ta was at 57% on the front tires (it's a rumor i could be wrong). if i am right then throwing a 12 bold or a 9" would be ok. the idea goes adding weight is a bad thing no mater what, adding weight but increasing reliability is better then a hot stick in the eye, adding weight in the rear of the car is the only acceptable place to add weight if you need to do so. ideal situation you would want to replace your 10 bolt with a irs like off a gto. if your going to stick with a solid axle handling is all in the differential. 10 bolt 12 bolt 9" it doesn't matter. a spool will make your car handle like **** and give you dangerous over steer. a locker will do the same. ideally you will want a viscus or a lighter clutch type lsd to allow the tires to spin at different speeds in the bends. i would recommend weighing your car. check your cross weight if your in the 50-51% range stick with a 10 bolt. if your in the 52-57%+ go with a larger rear end.
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I have a Moser 12 bolt with a Truetrac. I don't like it due to the bizarre torque arm mounting and high spring perch.
Have you looked into getting a Midwest Chassis Fab 9" with aluminum center?
Have you looked into getting a Midwest Chassis Fab 9" with aluminum center?
Last edited by qwikz28; 06-07-2011 at 08:21 PM. Reason: No one wants a 9' rear. That's too big
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Right now, I'm just researching to find what most guys are running. Obviously, I do have a budget, but I don't want to skimp on that major of a purpose. I've just been hearing that with my recent motor swap(h/c/i ls6), my rear end will probably take a dive soon. ....besides...Its a hard driven 136k miles old. I'm looking to replace it with a unit that will accommodate fairly high hp and autox....I'm not into drag racing.
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I run a 31spline 9inch with an iron section and Trutrac. Yeah its heavier and you have to make some room to fit. But other than I just drive the tires off it.
If I had to do it all over again, I would ensure I get the 9inch with tapered roller axle bearings instead of the standard ballbearing axle bearings. The ballbearing axle bearings wear out fast when autoxing and playing on the road tracks.
If I had to do it all over again, I would ensure I get the 9inch with tapered roller axle bearings instead of the standard ballbearing axle bearings. The ballbearing axle bearings wear out fast when autoxing and playing on the road tracks.
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I'll be going with a Midwest Chassis 9". Even with an iron center section, they told me it would only weigh about 10-15 lbs. more than a stock 10-bolt. With an aluminum center section, it might be lighter than a 10-bolt.
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The '63 (C2) was the first year of the IRS in the vette. At that time they had one trailing arm per side, and the trailing arms also controlled the toe setting.
The design remained very similar until the C4, which had a separate toe control, and two additional trailing arms were added. The C4 components were also made of aluminum instead of steel. The C4 is what is pictured on the 94 firebird in the picture.
The C5 was the first of the true SLA set ups. Even if you could put an IRS on a road race car, in what class would it be legal, and would it be competitive if everything else on the car remained the same?
The design remained very similar until the C4, which had a separate toe control, and two additional trailing arms were added. The C4 components were also made of aluminum instead of steel. The C4 is what is pictured on the 94 firebird in the picture.
The C5 was the first of the true SLA set ups. Even if you could put an IRS on a road race car, in what class would it be legal, and would it be competitive if everything else on the car remained the same?