Well I'm running the 454 and 455 springs for a 3800# B-body with no snubber and XL9000 Rancho shocks. They seem to work good for me with the shocks set on 6 shruggy
Gus beer

rear view savoy.jpg

64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
Dana 60