I have a 94 Formula and was thinking about putting some 4.10 gears in the rear end. I've heard that the stock rear end is weak and breaks easily.
If I put in a 4.10 gear setup would the stock rear last?

I saw a 12 bolt on CL for $450
Chevrolet, 12 bolt rear with 411 posi gears, brake drum to drum, 54 inches, in excellent condition
Came out of Chevelle or Camaro

Would this work on my car? I could cut and reweld the spring perch, but I don't want drums how could I put discs on it?

If anyone could give me a few pointers it would help out a lot. Thanks

 

do a search for all your questions.

 

I dont know if it would ever work? Even with lots of fab work.

Search "beefing up the 10 bolt" or something along those lines and you will find lots of threads with people who are sticking in better axles, welding the tubes, solid pinion spacer, etc.

and others who say any money spent on the 10 bolt is a waste. So it is up to you.

 

You could make the 12-bolt work with significant fab work. In addition to the spring perches you'll have to add provisions for the torque arm and the panhard rod. The conversion to disc brakes is pretty easy, just copy what's on the 10-bolt you have now...

 

The rears can break easy if you beat on them too much. Mine has been fine, even with 4.10 gears. I did go to a 12 bolt back in the late '90's but swapped it back out a year later for my original 10 bolt since I couldn't cut any better short times with it. Still hanging in there

 

With your mods you will be fine on the 10 bolt... just don't go launching on slicks at the dragstrip. 4.10s are a good gear for the M6 cars.

You need to fabricate that 12bolt for the torque arm- not easy.