Auto-X / Roadrace rear suspension 1969 Valiant
Not really keen on the triangulated 4-link due to what you stated. Binding, less articulation. It does fine on a street car where an off ramp or clover leaf is as tight as you get but I am after optimum track suspension. I do see than Reilly went to a swivel-link (rebuildable greasable heim joint) that may help a fraction with binding but the articulation is still limited by the uper bars and their angles.
Great point on using sliders. Some of the reasons I like the composite monoleafs: Cheaper, can buy multiple spring rates. Lighter, can lug multiple sets to the track and swap them out. With a panhard rod you eliminate the side to side movement of the rear axle. I totally forgot about the sliders, thank you.
BTW, I thought the Gurney cars ran composite monoleafs. I was mistaken.
Tom Kaman ( Purple Valiant) , who just had his bad *** 70-71 Firebird built by George is running the same TCI/ torque arm suspension and has been winning this year. To my knowledge none of the cars in NMCA Classic American Muscle class are running an independent rear. All solid axle with various rear suspensions. I do believe Mary Pozzi is running an Art Morrison IRS but she is sponsored ($13,000 rear suspension) and runs in SCCA and OUSCI.
If I had F@(% YOU money I would be running the suspension she does, front and rear. IT is way above the capabilities of a torsion bar/ leaf car.
One of the foundational principles of this Valiant build was to continue on with a Valiant that would have been the result of Tom's car if he had continued refining it. I talk to him often about his thoughts on taking it further. We are friends and I see him every once in awhile at the shop. He had an 833 and said he would have gone T56 had he continued so I put that on my shopping list. He would have went with a bigger torsion bar so I went with 1.24" bars. Brakes? He likes my Viper kit. His engine was underpowered so I made sure to have Brian at IMM build an engine specifically to tackle not only autocross but big tracks as well. His car was pretty balanced but he said he would have liked to get a little more weight off the nose so I got a fiberglass hood and may get a fiberglass front bumper.
I have an Alter-k-tion car but I really wanted to stay away from a coilover suspension and build an OEM suspension Green/Red Brick inspired Valiant. Then I met Tom and saw him coming onto the San Diego SCCA scene. By the time I was close to done collecting parts and ready to get chassis work done he had told me that he would have liked to try George's 3-link before selling it. The whole reason he got out of that car was to move onto a different platform that would be more competitive. GM F-bodies. His Valiant was competitive for a moment in time but this sport is ever changing and where we are today, if you want to be at the top of the heap you have to be in a platform that is well supported and be a damn good driver (which Tom is). He could not be competitive in the purple car today. I won't be able to ever be #1 in my Valiant but my particular goal is not to be class winner but to have the fastest Mopar to compete in the class and take out as many brand X cars as possible. I would have to spend $50,000 on suspension and chassis work to be competitive in a Mopar and it would mean not using ANY Mopar parts other than the body and perhaps engine.
Not worried about intrusion at all really. I share your concerns with the XV stuff. There are some other things I don't like about it. The lower bars for one would need to be put in the frame rail like the MP inboard relocation. The Reilly Motorsports has an option for OEM mounting location at the front spring hangers or inboard, for which they sell the the frame cut-out. I had seen right off the bat where some changes to the XV kit would be needed. Illiminates a lot of the allure for me.
Not really keen on the triangulated 4-link due to what you stated. Binding, less articulation. It does fine on a street car where an off ramp or clover leaf is as tight as you get but I am after optimum track suspension. I do see than Reilly went to a swivel-link (rebuildable greasable heim joint) that may help a fraction with binding but the articulation is still limited by the uper bars and their angles.
Great point on using sliders. Some of the reasons I like the composite monoleafs: Cheaper, can buy multiple spring rates. Lighter, can lug multiple sets to the track and swap them out. With a panhard rod you eliminate the side to side movement of the rear axle. I totally forgot about the sliders, thank you.
BTW, I thought the Gurney cars ran composite monoleafs. I was mistaken.
For all these years I was under the assumption that the chassis man was going to do a 3-link. George (my chassis guy) won NMCA-West autocross in 2021 in his torque arm rear / Total Cost Involved front suspension 69 Camaro so he said he wasn't recommending the 3-link anymore. If you pay attention to NMCA West and OUSCI you would see many cars that are way up there in refinement.
Tom Kaman ( Purple Valiant) , who just had his bad *** 70-71 Firebird built by George is running the same TCI/ torque arm suspension and has been winning this year. To my knowledge none of the cars in NMCA Classic American Muscle class are running an independent rear. All solid axle with various rear suspensions. I do believe Mary Pozzi is running an Art Morrison IRS but she is sponsored ($13,000 rear suspension) and runs in SCCA and OUSCI.
If I had F@(% YOU money I would be running the suspension she does, front and rear. IT is way above the capabilities of a torsion bar/ leaf car.
One of the foundational principles of this Valiant build was to continue on with a Valiant that would have been the result of Tom's car if he had continued refining it. I talk to him often about his thoughts on taking it further. We are friends and I see him every once in awhile at the shop. He had an 833 and said he would have gone T56 had he continued so I put that on my shopping list. He would have went with a bigger torsion bar so I went with 1.24" bars. Brakes? He likes my Viper kit. His engine was underpowered so I made sure to have Brian at IMM build an engine specifically to tackle not only autocross but big tracks as well. His car was pretty balanced but he said he would have liked to get a little more weight off the nose so I got a fiberglass hood and may get a fiberglass front bumper.
I have an Alter-k-tion car but I really wanted to stay away from a coilover suspension and build an OEM suspension Green/Red Brick inspired Valiant. Then I met Tom and saw him coming onto the San Diego SCCA scene. By the time I was close to done collecting parts and ready to get chassis work done he had told me that he would have liked to try George's 3-link before selling it. The whole reason he got out of that car was to move onto a different platform that would be more competitive. GM F-bodies. His Valiant was competitive for a moment in time but this sport is ever changing and where we are today, if you want to be at the top of the heap you have to be in a platform that is well supported and be a damn good driver (which Tom is). He could not be competitive in the purple car today. I won't be able to ever be #1 in my Valiant but my particular goal is not to be class winner but to have the fastest Mopar to compete in the class and take out as many brand X cars as possible. I would have to spend $50,000 on suspension and chassis work to be competitive in a Mopar and it would mean not using ANY Mopar parts other than the body and perhaps engine.
