I am just too limited in build knowledge to figure this out and I'm sorry if this seems too hazy or too basic for anyone. I recently acquired a 32 Tudor with an 85 Corvette rear suspension. The builder got rid of the transverse spring and converted to coil-overs. The top mounts are way too forward of the axle centerline for my comfort......but.....thats another issue. The coilovers are shot including the bushings. The old ones have no markings or numbers of any kind. What measurements do I need to give to suppliers like Pete&Jakes etc to try and find some replacements. I have no idea on the spring rates. Any suggestions on whether or not to junk the whole suspension and start over or convert back to the leaf spring. I have little to no experience with independent rears and am just lost with this. Looks like I could relocate the top shock mounts but I would have to weld in a cross member closer to the axle centerline I think. Any help for this 67 year old rodder would be appreciated.
I would talk to the folks at Aldan or maybe call Don McNeil at Flatout Engineering. he has been doing Vette IRS conversions for years and has lots of knowledge. be careful about the shock mounts though, if you move them that could change the spring rate as well.
Seem to remember that the Speedway catalog has charts for selection of shock and spring rates. Even has 'example' cars. You can then tune with spring length adjusters. Also shows how angle effects spring rate.
most of the rod suspension suppliers can work with you to determine a spring rate, given the weight of the vehicle. some coilovers can be adjusted by screwing one of the mounts up or kown the body with a spanner wrench to fine tune. you will need the mount-to-mount measurement with the suspension at static height - with the halfshafts level. and the angle of the shock. I don't follow what you are saying about the "too far forward" need pictures or someone could come by.
Thanks Hambers, I'll check with some suppliers. What I meant by "too far forward" is that the upper mounts are way off of vertical torward the front of the car. Its probably a 30 degree angle and just looks to put too much rear force on the suspension on deflection. I am not an engineer but more used to vertical or nearly vertical mounting. I tried one specialty Corvette suspension company that sent me some new coilovers and special mounts but they dont fit for some reason. He has tried two times but still not gonna work. The mounting brackets will not fit the mounting flange on the suspension.
Just measure the compressed and extended length of the shock (bolt hole to bolt hole). Any knowledable shock guy should be able to match them up by those lengths. The springs should be re-useable and the spring rate may be etched into the end of the spring. If so, give that info to the shock guy and that should help with getting the right valving. Forget that it's on a Vette suspension on a 32. It's just a shock and spring... You're right about the upper mount, but it really shouldn't be a problem at that angle.
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