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FC rear camber gain

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Old Aug 9, 2005 | 09:52 PM
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FC rear camber gain

I was wondering if anyone has ever actually ploted rear camber gain as the suspension goes into compression. My main concern is with excessive camber gain as the car squats in a drag racing set-up. I have video tapes of my car during a launch at the drag strip and the rear squats substantially.

Current setup consists of stock springs and Tokico adjustable struts with the fronts on full soft and rear on full firm during racing. Bogart wheels and MT drag radial tires in the rear.

Thanks,
Andrew
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Old Aug 10, 2005 | 07:40 AM
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I've been meaning to measure everything and put it into SolidWorks (3-D CAD program), but haven't gotten around to it yet.... Heck I just transfered the title yesterday and I've owned the car for 3 years.
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Old Aug 11, 2005 | 09:08 PM
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Anyone? Its hard to imagine that noone has actually measured this. Any guesses? 1 degree per inch of travel? 1/2 degree? more? less?

Andrew
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Old Aug 12, 2005 | 12:23 PM
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Originally Posted by andrewb70
Anyone? Its hard to imagine that noone has actually measured this. Any guesses? 1 degree per inch of travel? 1/2 degree? more? less?

Andrew
For a rough answer, you can measure the camber, lower the car in 1/4 increments, and get the rough gain. You can grease the shock piston just before running to see how much squat you are getting on launch. If I were drag racing an FC, I'd make friends with crispeed, and get that sort of data via the friendship . Carl
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Old Aug 14, 2005 | 09:21 PM
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Thanks for the help. I was trying to avoid going through the process of taking the measurements. It's a little surprising that noone has done this before.

Andrew
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Old Aug 14, 2005 | 10:21 PM
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From: Vtech
i don't think many people in this section are drag racers, but the information is beneficial to all racers so who knows. How about some 2-piece uprights?
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Old Aug 15, 2005 | 08:22 PM
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What would a 2-piece upright do for you?

Andrew
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Old Aug 16, 2005 | 06:47 PM
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From: Vtech
do a search for michelin formula one two peice uprights.
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Old Aug 16, 2005 | 07:16 PM
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Uprights? The rear suspension is a semi trailing arm multi-link thingie, not double a-arm like F1 cars.
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Old Aug 16, 2005 | 08:59 PM
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From: Vtech
i know that, but that's the only way to eliminate camber gain on acceleration and still handle well
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Old Aug 17, 2005 | 10:55 AM
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What about anti-squat?
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Old Aug 17, 2005 | 11:12 AM
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Then you eliminate weight transfer needed for additional traction when launching.
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Old Aug 17, 2005 | 11:16 AM
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Travis R's Avatar
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No you don't. Weight transfer is unaffected.
The only things involved with weight transfer are CG height and wheelbase (or track width for lateral transfer).
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Old Aug 18, 2005 | 11:52 PM
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Yeah it's a common misconception that weight transfer is related to the amount that a car dips or sways during acceleration. The stiffness of your suspension does absolutely nothing in regards to weight transfer.
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Old Aug 19, 2005 | 01:53 PM
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You two are correct, sorry for the misinfo.

fwiw, Longitudinal Load Transfer = Acceleraction(g) x [(Weight x CG Height) / Wheelbase]
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