1974 Scamp - Swapping 7 1/4 to 8 3/4 Questions

[74GreenScamp]

Hello everyone! Some questions for my A body folks.

1.) Can I use the drum brakes from my BBP 7 1/4 on the 8 3/4
2.) What leaf springs do you run? I love an a body sitting higher in the rear. Looking for springs that will sit a few inches higher than stock and provide decent ride with great traction capabilities. Include pictures of your car with the springs if possible.
3.) I am having a B Body 8 3/4 housing cut down to fit an A Body (Dimensions: Flange to flange- 52 5/8, Spring perches center to center- 43). With that, do I have the spring perches welded at 0 pinion angle or is that dependent on what leaf springs I use?

I look forward to reading you responses. Thanks!

 

[TF360]

A few guys here have used ESPO Springs, and you can get them in +1, or +2 to lift the car a couple inches in the rear. The +1's look like they raise the car a couple inches. I would call them.

 

[jrc4y4]

When I swapped from 7.25 to 8.25 I called Espo. I got the one extra leaf. The lady on the phone knows her stuff and recommended adding an inch. However I held off at fear of getting too much rake. The extra leaf takes almost a half inch out of height because of how the rear end mounts. So worn out springs sat similarly to new springs either an extra leaf. Here’s how it looks. I don’t hate it but I do regret not listening and adding an inch. FWIW I could adjust my torsion bars to lower the front and get a slight rake. Car has about 300hp and 3.92s and hooks pretty well. Zero wheel hop. Happy with Espo and would buy them again.

 

[72bluNblu]

1- Yes, you can use the brakes from your BBP 7.25 on your 8 3/4. All of the BBP brakes and axles use the same axle flange offset. The backing plate might only have 4 holes on the 7.25, but drilling the 5th hole (if it isn't already there) is all you need to do.

2- I run AFCO 20231M's. They're a 121 lb/in spring that's been discontinued. I use spring sliders in the back that lowered the car about 3/8" from there. The AFCO's use the factory arch, although if anything I'll probably add 1/2" lowering blocks

3- You would not want to use 0° for the pinion angle. The factory pinion-to-perch angle for an A-body 8 3/4 is 5° up, which with the factory springs/ride height/driveline angles gives about a 2° down pinion angle. Also, IIRC the B-body perch angle was not the same as the A-body perch angle, so don't copy that either.