Auto-X / Roadrace rear suspension 1969 Valiant

Great responses guys. So it seems that, from consensus, that spring toe in should a) be minimal to keep forward bite and b) may not be needed if using a panhard rod. However, if toe is incorporated I would want to seriously consider keeping it consistent with E-body toe angle or less. Also, keep spring boxes and sliders in-line with the toe angle.

I will reach out to AFCO and try to speak to someone in regards to 72bluNblu’s attachment. I will ask how much that applies to a left-right turn / pavement application.

The results of today’s phone calls were a good conversation with Hyperco. They couldn’t help me out on the spring rate, all they carry is a 170 pound spring and don’t do custom jobs.

He did tell me about a vendor that specializes in Vette suspensions called Vansteel. They do coils and mono leafs for various Corvette generations. Al, at Hyperco, told me Vansteel had bought a Chrysler mold from Hyperco.

I was able to talk to Eric at Vansteel and he said they couldn’t get something going on the Chrysler springs until early summer 2023 but it sounds promising. I told him that there was a growing number of enthusiasts doing or wanting to do autocross in A-body Mopars and he could possibly find some customers that were looking for custom spring rates. He did go into a little bit about how composites react a little different (faster) than spring steel. He said 120 pounds seems light to him and some of his Corvette customers are using 150 and tuning with a double adjustable shock. He says you usually go a little heavier with composites for the same application than multi-leaf steel.

He is going to email me by Wed. next week to confirm he has laid eyes on the Chrysler mold. I told him about the Hotchkis double adjustable shock offerings and some of the torsion bar sizes that are popular with performance handling Mopar A-bodies. I did not talk to him about the toe in idea or sliders. It was just a quick call and we agreed talking more in the coming weeks would likely flesh out many questions and thought. He will email me with confirmation that they still have the mold and wants me to reply with any information I can think of. He wants torsion bars sizes, wheel rates, wheel base, weights, … anything I can think of as far as vehicle dynamics.I plan to get the Valiant’s corner weights from Tom. I have found wheel rates for different torsion bars somewhere before (maybe Firm Feel?). I will also pass along the AFCO attachment to get their take on it.

Their bread and butter is autocrossing Corvettes and suspension tuning. He seemed interested in this foray into the Mopar composite leaf spring market. I welcome any information any of you can provide in regards to vehicle dynamics.

I also called Flex Form earlier in the morning and left a detailed message. I had a missed call from them this afternoon. Google maps says they’re permanently closed but the voicemail said that he listened to my message and looks forward to working with me to fill my needs.

It was a good day and have two possible vendors now. Re-looking at how the thread started I am just going to focus on this option. It has more going for it than the other options, IMO. Cheaper, lighter, faster spring action, easier to fabricate than other options, springs are possibly available right now through Flex Form, sliders available, frame boxes available, double adjustable shocks available, it’s somewhat OEM style suspension, ….. I’m just going to run this down and if Flex Form can get me a composite spring in short time that’s not a drag race leaf I will pull the trigger on the sliders, shocks, splined sway bar, and frame boxes.