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joedoozer
09-21-2011, 12:24 PM
I have seen some threads about the weight split between front tires, and I know what the base line set up calls for on my car. But I was wondering about the effects of Cross Weight. In what situation would you want an even split across the front tires, or a heavier RF than LF? In what situation would you want a Cross % to be 52% or 53%, as opposed to the base line of 50.5%?

jedclampit
09-21-2011, 01:05 PM
The split in the fronts/ cross weight varies with amount of left side % for a set bite and rear #.

joedoozer
09-21-2011, 01:10 PM
The split in the fronts/ cross weight varies with amount of left side % for a set bite and rear #.

I know that.

My question was. When would you want a heavier RF than LF. Or a cross % of 53% instead of 50.5%.

Matt49
09-21-2011, 02:21 PM
If you increase your cross% to 53% and don't change left% or rear%, you will have to have also increased LR bite.

Cross% and LR bite are mathematically linked. If you change one the other has to change unless you change left% and/or rear% at the same time.
The same concept is true for LF/RF split.
So if you get your LR bite where you want it and then go messing with the LF/RF split and DON'T change left% or rear%, your LR bite is going to change also.

dualdj1
09-22-2011, 09:25 AM
when you add cross, you're placing more weight on both lr and rf, which plants those wheels more when your car is riding on the springs. If you run a 4 bar, your lr changes will mainly have an effect off throttle, and to a much lesser extent on throttle. RF changes will have an effect both on and off throttle. so you want to add/remove cross with RF when you want to effect your corner middle/exit.

the same works with lf/rr weights (and shock adjustments). LF affects off throttle running on springs, and to a much lesser extent on throttle depending on how much hike you get. RR effects both on/off throttle.

I know that doesn't specifically tell you what to do, but look at where in the corner you want to adjust the car, and you'll figure out what to try.

joedoozer
09-22-2011, 11:09 AM
I don't know why I didn't just PM you in the first place haha. Thanks.

dualdj1
09-22-2011, 02:55 PM
Always good to have others look at what I say to make sure I'm right (which i'm not sometimes, lol).

croston71
09-24-2011, 07:47 AM
Whenever communicating with another fellow how can we safely assume he/she is or is not applying throttle? A spring may take varied forms but rates are measurable. I believe the advantage to thinking in terms of cross wieght rather than wedge is the fore thought that front needs attension simutaneously. How would one measure pressure applied to rear &/or front tires when the car is upon the vertical supports/lifts;bars?