1970 Chevelle Pro Touring Build

[David LaBuda]

As an average rule of thumb with our suspension kits we recommend 550 for small block and LS cars and 650 for big block cars. On my 3550 lb G body wagon I currently run a 600 lb standard coil spring. It definitely rides stiff compared to original springs if that's what you have in there now. I'm switching to coilovers and am going with a 550 spring so I can use that little extra bit more of body roll to plant the tires on the autocross, and that will give me a little more adjustability in the shocks to play with.

My suspension sensai taught me that stiffer springs are better in road course situations to better control the roll in high speed longer sweeping curves. Tuned and adjusted properly shocks help more in short fast turns like in an autocross. There's a bigger explanation than that, but so far what I've experienced he was right.



I know a fellow that had 550s in his G-Body Malibu and couldn't get the car as low as he wanted. The coilover shock manufacturer recommended he go to 450 lb springs and the car dropped more. That car was not a racer, just a LOW street cruiser so it worked for him. For a big heavy Chevelle like yours 425 sounds way too light unless you want a grandma ride, or are of the new style of thinking that lots of suspension dynamics (more body roll) will be put to work to plant tires. If that's the case the whole suspension needs to match that theory, spring rate, shocks, and sway bar choices. Ron Sutton likes this theory, he might be a good one to talk to to learn more about it.

Hope this gets you thinking...

Do standard coil spring rates directly translate to coilover spring rates? If so, I guess I'd be looking at 525-600 lb/in springs? I need to place the order tomorrow so any last minute advice would be greatly appreciated!

[Ben@SpeedTech]

Hey David-

Sorry I missed your question. You've probably already gotten an answer to the question if you placed your order, but yes, a 500 lb spring rate coil spring and a 500 lb spring rate coilover are the same, both will require 500 lbs to compress the spring 1".

[Agent_Orange_Shuvel]

Awesome build man, I joined just so I could subscribe to your thread and see how you finish this thing up