12:05 Garage- ’70 Duster build

lol! If I had a dollar for every time I went out to my car in my pajamas to measure something I could probably buy a HellCrate for it!

Ok, so with a motion ratio of .807 and a 450 lb spring you should end up with a wheel rate of ~293 lb/in, which is really close to the 300 lb/in wheel rate I run with my 1.12” torsion bars.

Your previous 400 lb/in bars have a wheel rate of ~260 lb/in

I think the 450 lb springs should be a pretty good improvement for you, certainly should cut a little more body roll and give you a good base rate to tune from. There’s still probably more room to go higher, but it will depend on your tire set up and compounds. With the Azeni 615’s at 200 treadwear on my Duster and 275’s up front I’m back to being able to put a little roll into it with spirited mountain road driving. I have a set of Firm Feel 1.18’s sitting in my shop, that’s a 370 lb/in wheel rate. I talked to Firm feel about it, I’m a little skeptical about that big of a jump in WR but they seemed to think it wouldn’t be as crazy as it sounds. Maybe I’ll have to go with some adjustable shocks at some point.

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Here you go! Yeah my factory ‘74 retractors were inside the quarter structure behind the door. But the mechanisms were a PITA so I replaced them with the ones from seat belt planet. I just mounted the retractors to the floor where the lap belt anchor was, I don’t recall exactly why I didn’t try to put them in the quarter but they work fine on the floor
Thanks for the comparison. I had 1.08 sway away bars.

Double adjustable shocks are the $hit! Besides being able to tune it on the track, I love that I can tame it down for normal street driving. I will get some for the back in the future.