Is this true with a 12 bolt too?

 

As far as if the car is stock, I wouldnt worry about it other than the better brakes from 89 up. If you are putting out some decent power or plan to it is not a bad option. I picked up my 3.45 9 bolt from an 87 GTA for 375. I couldnt leave well enough alone though so I upgraded to the 89+ brakes. LOL. I am going to be putting a t56 in this weekend so I may step up the gears soon. Over all it just depends on what your plans are for the car. If you are going to be putting out massive horsepower and have a wallet to match there is also 9" rears and 12 bolts to choose from. Miles(from 9bolt.com) has a 500 hp 427 in front of his 9 bolt and it has been fine for a few years now. He is also working on making some heavy duty parts for them too so they are definately an option if you are going to make more power than the 10 bolt will hold.

Ben

 

The car has a tired 305 and I will prolly put a 355 in it in the future. I would like to have a rear that would hold with drag radials.

Will my existing brakes bolt up to a 9 bolt or would I have to use the 89 up disc brakes?

 

Your existing brakes will work on a 9 bolt as long as it is from 85-88. If it is from an 89 you will have to get different backing plates for the brakes but they can still be used.

Ben