Lower body or raise diff?
Thread Starter
Burning Brakes
Joined: Apr 2002
Posts: 1,105
Likes: 113
From: Lawrenceburg, KY
Lower body or raise diff?
1979 Coupe - frame is getting a full weld/gusset job and I'll be installing a 6 point roll bar.
I'm replacing the rubber body mounts with aluminum. The aluminum mounts are 68-72 replacements and are about 1/2 the thickness of the rubber bushings. As such, the body is going do be "lower" than it was with the 79 rubber bushings. However, I'm also going to be solid mounting the rear diff and therefore have the option to raise the diff (I may even convert to the later aluminum batwing mount).
Am I better:
I'm replacing the rubber body mounts with aluminum. The aluminum mounts are 68-72 replacements and are about 1/2 the thickness of the rubber bushings. As such, the body is going do be "lower" than it was with the 79 rubber bushings. However, I'm also going to be solid mounting the rear diff and therefore have the option to raise the diff (I may even convert to the later aluminum batwing mount).
Am I better:
- Using the 68-72 bushings, letting the body come "down" and limiting the amount the diff rises?
- Machining new (thicker) bushings, keeping the body "up" and letting the diff come up more?
Last edited by ChrisLSx; Oct 29, 2020 at 02:38 PM.
Drifting
Joined: Aug 2015
Posts: 1,939
Likes: 476
From: NSW, Australia
C3 of Year Finalist (track prepared) 2019
Are you also lowering the suspension (ie using a longer bolt or whatever)? If so, then raising the diff will improve the rear suspension geometry, particularly toe change in bump. If you're not planning to lower the suspension then there's not really a gain in raising the diff. Personally, I'd lean towards doing both and then lowering the suspension less, butthat assumes that you're looking to lower the car a reasonable amount - it depends on how much you want to lower the car overall and what your aims/goals are.
Thread Starter
Burning Brakes
Joined: Apr 2002
Posts: 1,105
Likes: 113
From: Lawrenceburg, KY
Are you also lowering the suspension (ie using a longer bolt or whatever)? If so, then raising the diff will improve the rear suspension geometry, particularly toe change in bump. If you're not planning to lower the suspension then there's not really a gain in raising the diff. Personally, I'd lean towards doing both and then lowering the suspension less, butthat assumes that you're looking to lower the car a reasonable amount - it depends on how much you want to lower the car overall and what your aims/goals are.
Thread Starter
Burning Brakes
Joined: Apr 2002
Posts: 1,105
Likes: 113
From: Lawrenceburg, KY
No LS in this car. Over the past 20 years I've had a half dozen different vehicles (currently have a C5) with LS motors, but I'm going different (for me) with this 79. It's currently got the factory L48 and automatic, but that's being replaced with a 496 and a T56.
