Originally Posted by BillyShope
As someone has already pointed out, you already have a suspension layout similar to the NASCAR Cup cars. With approximately the same weight and CG height, there's no reason why the car can't be made to handle. Of course, if you want it to handle like a sports car, you have to accept the same level of harshness. Even a stock Miata has a harsher ride than a conventional car.
I'll replace the bushings on those support arms and concentrate my modifications on the springs and shocks layout. I didn't mean it would be doomed to handle like Holstein in a mud wallow. It's just that big, heavy body stuck up in the air and the fact that I don't want a ride so stiff you can count pebbles means that the car will never be king of the curves. As you point out, if I accept a harsher ride, I can improve the handling.
Every design is a collection of compromises. The feedback I've received here has convinced me that this rear suspension design doesn't have any compromises that interfere with my goals. Because of how much I don't know about suspensions, I was afraid I had the automotive equivalent of a conestoga wagon suspension under it.
Originally Posted by Frisco
Here are a few thoughts from me. Back in 1959 I owned a '50 Olds Coupe. It had a '56 Olds engine, '38 Cad/LaSalle trans with Corvette shift linkage. Suspension was basically stock except for cut coils in the front to lower it about 3". I ran the largest rear tires I could get at that time (8.20-15) and the rear wheel wells were radiused (Full radius). You might consider this for ease of rear wheel removal if you do lower the car as much as you mentioned. That car rode great and although I never tried any high speed type road racing, it handled very nicely. I did have new shocks on it.
As to the strength of the rear end; I believe your '49 rear is the same as the '50. If that is the case, third members from both Olds and Pontiac up to 1956 will interchange. That third member/rear end assembly was "the way to go" at the time ('50's thru '60's). It was the "9" Ford" rear of that era and is plenty strong for the application you have described.
I'm 47 years behind and 2 weeks ahead of you on the radiused rear wheel wells.
See what's wrong with this picture?
the 49-flames-8.jpg attachment.
In the shop manual, it talks about the differences between the internals of the rear end used for the 6 and the 8. You were likely dealing with a rear end from a "Rocket 88" or 98. I'm still a little nervous about hooking a high torque big block to that old differential. I'd prefer to be able to use engine, transmission and rear end from a donor car.