Track Suspension help
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Joined: Feb 2011
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From: Plano, TX / Pagosa Springs, CO
My car maxed out around -2.7 one side and -2.9 on the other side before losing safe thread engagement.
A good friend of mine had the same issue.
- Chris.
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Joined: Apr 2014
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From: Jessup, MD
It depends on how the top plates are set on the front strut tower slots. Setting "inward" on the slots will yield more thread engagement for a given camber angle. The thread size is M14x1.5. In my opinion >20mm of engagement is ideal, which this depth is almost 150% of the thread diameter.
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PCA National Instructor
TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion
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Joined: Apr 2014
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From: Jessup, MD
^ this. Every car is different depending on how the subframe is centered to the strut towers.
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From: Jessup, MD
Tom,
We are going to modify my TPC toe links to do a rod end on the outboard side to get back some wheel clearance. I am running an 11.5" wheel that is 19" OD. The Tarett toe links employed a rod end on the outboard side and did not have interference at my wheel. The TPC version does. I will report back our results.
- Chris.
We are going to modify my TPC toe links to do a rod end on the outboard side to get back some wheel clearance. I am running an 11.5" wheel that is 19" OD. The Tarett toe links employed a rod end on the outboard side and did not have interference at my wheel. The TPC version does. I will report back our results.
- Chris.
We have done a similar experiment. The knowledge we gained from the experiment was that it was a compromise between improved vehicle performance via better bump/rebound geometry versus addition grip from wider wheels/tires. By "forwarding" the center of the ball joint closer to the rear upright in order to create more clearance to the inner wheel barrel the toe curve goes farther out. But with a wide enough and sticky enough tire the grip threshold is raised via friction to mask the issue until the tire grip starts to go away. If I were to setup a car solely for the purpose of setting qualifying position time for a race with fresh tires then I'd go wider over geometry. As oppose to if I want a car to be optimized for the last quarter of a race when the tires are fading then I'd go with better geometry. #racestrategy
Would love to hear your results for your usage!
Below are random photos from our experiment including cutting an OEM link to extract the ball joint. We believe the front and rear ball joints are identical. Different height shims were used to tune the toe curve. And shallow head bolt for better clearance to wheel barrel.
