Hi, I'm new here... I have a 88 Monte SS and just finishing a 406 which will definitely limit the stock 7.5" rear that is in there now. I have a 8.5" rear that needs new spiders, but other than that is ready to go... this one is out of a 73-77 MC.
My question is does anyone have/make control arms to make this a direct swap?
The car has a Turbo 350 in it that will be staying for a while, but I do have a 700r4 which might find its' way home under there.. will I need to modify the driveshaft that is under there right now as well?
I am going to run the 7.5" until the end of breakin period.... at which point it is probably going to self destruct, so I have some time, I just want to make sure I know what I need before it happens!
Thanks,
Bear
Rear end swap...
Re: Rear end swap...
Hi Bear, thanks for using the site and helping others by asking your questions.
Now the rear you have is a 73-77 a-body, which is not a very god fit for your car. A 1965-1972 rear would be a better fit and they sell alot of retro fit parts for this abody to g-body application
-65-72 swap has upper control arm brackets you can get with not adjustment all the way to ful double end adjustment for unlimited pinion angle set-up. (WE CAN SUPPLY THIS IF YOU NEED)
-THE LOWER REAR SHOCK MOUNTS WILL NEEDA SLIGHT MODIFICATION , BUT i HAVE ALSO SEEN THEM used as is also.
-The spring perch pockets need to be center over the axle tube also...again I have seen them used as is.
NOW the rear you have 1973-1977 a-body midsize gm (grand prix, malibu classic, el camino etc)
- One of the biggest problems with this rear not fitting is the upper control arm mounting area...IT IS TOO wide to spead the upper arms to fit and the aftermarket has NOT produced a retro control arm to fit it. (WE ARE TRYING TO GET IT DONE THOUGH, THERE IS POTENTIAL.)
-Next the shock mounts are in the front of the axle tubes not the rear where your G-body care has them...this is another advantage to the early a-body 65-72 rears.
- Last the length is much wider than the early a-body 65-72 rear and of course your g-body rear.
So there is some info for you to use.
WE DO MAKE 12 BOLT REARS YOU CAN BUY COMPLETE THAT ARE A DIRECT BOLT IN ALSO ASK FOR A QUOTE.
Your best bet for a truoble free upgrade is to find a GN or OLDS 442 rear 8.5 that are a direct bolt in application . The drive shaft will be the only modification
Jim Mitschke
J D Race
Now the rear you have is a 73-77 a-body, which is not a very god fit for your car. A 1965-1972 rear would be a better fit and they sell alot of retro fit parts for this abody to g-body application
-65-72 swap has upper control arm brackets you can get with not adjustment all the way to ful double end adjustment for unlimited pinion angle set-up. (WE CAN SUPPLY THIS IF YOU NEED)
-THE LOWER REAR SHOCK MOUNTS WILL NEEDA SLIGHT MODIFICATION , BUT i HAVE ALSO SEEN THEM used as is also.
-The spring perch pockets need to be center over the axle tube also...again I have seen them used as is.
NOW the rear you have 1973-1977 a-body midsize gm (grand prix, malibu classic, el camino etc)
- One of the biggest problems with this rear not fitting is the upper control arm mounting area...IT IS TOO wide to spead the upper arms to fit and the aftermarket has NOT produced a retro control arm to fit it. (WE ARE TRYING TO GET IT DONE THOUGH, THERE IS POTENTIAL.)
-Next the shock mounts are in the front of the axle tubes not the rear where your G-body care has them...this is another advantage to the early a-body 65-72 rears.
- Last the length is much wider than the early a-body 65-72 rear and of course your g-body rear.
So there is some info for you to use.
WE DO MAKE 12 BOLT REARS YOU CAN BUY COMPLETE THAT ARE A DIRECT BOLT IN ALSO ASK FOR A QUOTE.
Your best bet for a truoble free upgrade is to find a GN or OLDS 442 rear 8.5 that are a direct bolt in application . The drive shaft will be the only modification
Jim Mitschke
J D Race
J D Race
Re: Rear end swap...
OTHER OPTION UPGRADE BUILDS YOU MAY NOT HAVE THOUGHT ABOUT, BUT SHOULD CONSIDER.
1) Use 28 spline axles in your 7.5 rear
2.) Aftermarket Dura Grip or Eaton posi unit with 28 spline for the aftermarket 28 spline axles in (1)
3.) Aftermarket gear set to handle more power
These options will make big gains in strength for your 7.5 g-body rear and will keep it running strong on the street and some track blasts.
The 7.5 rear is a good rear ad will do the job with these upgrades. YOUR BIGGEST AND ONE OF THE MOST IMPORTANT THINGS IS THE INSTALLATION OF THE PARTS. WITH OUT THE INSTALL CORRECT THE BEST PARTS WILL FAIL! PERIOD.
Good luck with your choices and we are always here for your help, questions, install combinations, etc.
Jim Mitschke
J D Race.com
1) Use 28 spline axles in your 7.5 rear
2.) Aftermarket Dura Grip or Eaton posi unit with 28 spline for the aftermarket 28 spline axles in (1)
3.) Aftermarket gear set to handle more power
These options will make big gains in strength for your 7.5 g-body rear and will keep it running strong on the street and some track blasts.
The 7.5 rear is a good rear ad will do the job with these upgrades. YOUR BIGGEST AND ONE OF THE MOST IMPORTANT THINGS IS THE INSTALLATION OF THE PARTS. WITH OUT THE INSTALL CORRECT THE BEST PARTS WILL FAIL! PERIOD.
Good luck with your choices and we are always here for your help, questions, install combinations, etc.
Jim Mitschke
J D Race.com
J D Race