10 Bolts - Discuss
 

Dont tell me Im an idiot. I am asking because I personally dont know the answer and I am curious.
The rears that are in F-Bodies from 82-02 are said to be terrible for withstanding even stock abuse. Which I believe from all the horror stories I have read.
Is there no way to use a 8.5 10 bolt from older GM's? Is it that difficult to get it to work on these type of vehicles?
There are a bunch of racers including myself running a 8.5 10 bolt housing with the tubes welded and have aftermarket high performance guts in them running deep in the 10's. Why cant you guys do this?

Obviously if I new the answer, I would not have posted this.

The problem is the TQ arm mount. I am sure you could fab up a TQ arm mount on a 8.5 and might be able to use it but there are better alternatives out there. They installed 9 bolt rears on certain Z28's and GTA T/A's in the 80's and early 90's but they are expensive to upgrade if you wanted a different gear. They are stronger then the 10 bolts and will bolt right into a 3rd and 4th gen. Other options are 12 bolt and 9 inch rears and also the Ford 8.8 rears are being converted into F-body rear ends.

You can also roll the dice and build a 10bolt and pray it doesnt break like I did!!

Another issue: i think 4th gen rears are a bit wider than most 8.5" applications. There are a few firms that are making torque arm setups for older cars (BMR maybe?) so maybe they have a way around the t/a issue

I can't see any of it being cost effective as just buying one that is made for the car.

Yeah, I think Kurt Urban was running in the 8's on a 8.5" 10 bolt a few years back with no issue.

Besides the torque arm mount, everything is on a small scale. The ring gear, the carrier, etc. The 7.5 was originally designed for a Vega. A light, 4cyl, compact car. Not a heavy powerful car like a 4th gen.

could do a 4 link to bypass the torque arm, no?

now you got me thinking, my bird race car... may be an idea... i wonder if the width of the lower LCA are the same distance apart in g body and f body cars. if so, then you only need to fab up upper mount for aftermarket adjustable g body upper rear control arms which are at a small angle off the diff. hmmm....

What is better having upper and lower control arms or moving the TQ arm off the tranny to the body? Thats what I always wondered.

Not sure if one is really "better" more than they are just different.

well i havent had a trans mounted TQ arm in a long time. i tore my stock oem tq arm years back with my stock motor setup, on the street, with street tires during a 1-2 shift. since then i have had a chassis mounted tq arm. car felt so much nicer afterwards, trans didnt rise and fall every time i got on or off the gas pedal, lol.

but now, i will seriously be looking into putting a stock-ish 8.5 10bolt in the bird with upper control arms. basically all i need is the section of a g body frame crossmember, and fab it in. In the bird, the gas tank will be getting taken out in favor of a fuel cell anyway so welding in a custom crossmember with bracing is a real possibility.

An 8.5" rear can be as strong as a 12 bolt. Trucks have 8.5" rings and 30 spline axles. Watch your width. Measure. Speedway motors will have a lot of the stuff you need to fab. Although in the long run you may gain nothing or even go backwards if you don't do it right. A torque arm setup is not a bad thing.

if you want to go that route you are better off using a mustang 8.8 and a Battle Box for a fox body. Remember, some of the fastest drag radial cars in the world have a torque arm some of them are even mustangs. Torque arms just plain work.

I wasnt saying to alter the suspension, just to see if you can fab the stuff on to an 8.5. I believe in the suspension/torque arm set-up, my brother never had a problem hooking in his car. The Drag Radial class is doing amazing things on stock style suspension.

The biggest Problem is the TQ arm mount.... By the time u find a rear and buy all the brackets/ fab up what you need your not to far behind a moser 12 bolt or 9in

How about using a pair of ladder bars to install the rear of choice instead of fabbing up a torque arm mount? Ladder bars are strong, and basically are short versions of a torque arm. Just weld them up.

http://static.summitracing.com/globa...ak-20460_w.jpg

"pete z" bars might make things a little easier

ladder bars will prevent the car from being allowed to run in any stock suspension classes if that is a consideration.

Yes, they would - but as mike pointed out, they would also keep you out of any stock style suspension racing.

- Justin