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View Full Version : RF Camber - Effect on RF Ride Rate?



TheJet-09
08-08-2015, 02:01 AM
Can or does changing your RF static camber setting (say from -4* to -5.5*), or increasing the RF camber curve (say shortening your RF upper control arm and resetting the static camber to the same as before) have an effect on the ride rate (incorrect terminology?) or "ease" at which your RF will compress? Without getting caught up on specifics (like control arm lengths), I'm trying to understand the logic behind this (if there is any). In doing the aforementioned, it seems like my car does not get over on the RF as easily as it did before, also indicated by less shock travel. And she sure didn't turn as well as before the changes, which is the opposite of what I was looking for. Any thoughts would be appreciated!

Matt49
08-08-2015, 09:19 AM
Because of scrub radius, increasing the camber curve decreases wheel rate which means you will get less shock travel for a given amount of weight transfer. Hard to explain but I'll try.
To calculate the wheel rate for a front wishbone suspension you need to know the lower control arm length, the shock/spring mounting location, and the shock/spring angle. The rest of the math you can find here:
http://eibach.com/america/en/motorsport/products/suspension-worksheet
With that being said, this assumes zero scrub radius and no change in the tire contact patch relative to the moving suspension components. If you have a camber curve and no scrub radius, it still might be pretty accurate. But as soon as you introduce scrub radius (which all late models have) to camber gain, the contact patch is moving relative to the suspension and this will increase as camber gain increases. Result is a softer wheel rate which is likely why your car didn't turn as well.

TheJet-09
08-08-2015, 12:45 PM
Thanks Matt! I'm putting everything back to where it was, but wanted to better understand what I had affected. I recall Rayburn having a "zero scrub" front end at one time. Sounded cool, but my understanding is we need scrub radius in our front ends. With none, you would actually have to break the contact patch loose in order to turn the wheel. I may be wrong, but it would obviously not be the first time!

MasterSbilt_Racer
08-08-2015, 04:46 PM
I have always found wheel rate reduced when I went to a more aggressive camber curve. Sometimes, it was obvious in the garage that it wanted to get on the rf.