I recently got a 78 z 28 as a project and I'm wanting to put a 98 z28 rearend in it any recommendations on how to convert the coil over suspension into leaf spring any advice would be greatly appreciated!!!

 

The 3rd and 4th Gen 7.5/7.625" 10-bolt rears are not very strong. What kind of power are you making?

The 4th Gen (93-02) version is 3" wider than the 3rd Gen version, and would require you to run the large (50 to 55mm) offset 4th Gen wheels, to keep the tires under the fender. The 3rd Gen version works with 0 offset wheels, like your 2nd Gen runs. The 3rd and 4th Gen rears are not "coil over".... separate spring, separate shock.

Both 3rd and 4th Gen rears are set up for coil springs, torque arm and a panhard rod. You would have to strip all the existing brackets, then weld on the 2nd Gen spring and shock brackets, hopefully keeping the axle tubes straight and not having them distorted by the heat. And you will end up with a rear that is weaker than the earlier 8.2" and 8.5" 10-bolt rears.

 

Not making any power at the moment just trying to get going the car already has a bad rearend

 

I don't think you are going to find anyone here who has done the 98 into 78 swap. Not a lot of 2nd Gen people on the site any more. If you want to try and get lucky, I can move this to the "Drivetrain" forum, because you aren't likely to get tech help in the "New Member Intro" forum.

 

Okay thanks

 

And why do you want to Change? The 8.5 10 bolt is just as strong as a 12 bolt.And is way stronger than the 7.5 rear end. The stock 1978 suspension with a new set of WS-7/Z-28 rear springs .A good set of gas shocks. 7/8 rear sway /1/14 front bar with a Herb Adams rear bar kit works quite well. but if you want to go coil overs There are other kits that keep you original rear end..