Solid bushing spring rates

[1977nova]

I am installing del-a-lum bushings on my car and I would like to know what spring rate I should get. I would like to have a 400 lb spring but thats with rubber bushings. I know the del-a-lums let the suspension work more freely so I feel I need a higher rate spring. I have a 1 5/16 sway bar so I dont wan't to go to a very high rate but I feel that 400 lbs is too low. I was thinking aroung 500 lbs but I am not sure if this is a good estimate.

[Zee]

I can't give you a recommendation but I can confirm that you are on the right track. I have Del's and used them with my stock 450 lb springs and my Formula rode like a Caddy. The performance of the stock springs combined with a big sway bars and dels was actually surprisingly good. I would have probably left them in if I had not cut 3/4 of a coil out. The car bottomed out all time.

I just finished putting in a set of Hotchkiss 600 lb springs as I think the 700 lbr's Global West sells would be too much. I hope to get it on the road soon so I'll know for sure.

[David Pozzi]

That was discussed a while back, I guessed rubber bushings add 20 to 30 lbs of spring rate per side. mean69 stated cornercarvers.com had a post that a guy tested his wheel rate with rubber bushings and no springs, and had results in that range.

I'd allow 50 lbs for the difference.

[1977nova]

Thanks guys, I think I will use a spring rated around 450 lbs. Would you recommend this with 5 leaf rears or should I go to a larger rate or would I be better off with the lower rate and changing my leafs? Oh and I am running a 7/8 rear bar.

Mark