Corner weight compromise?
09-23-2012, 05:35 PM
#81
Drifting
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Location: Dayton, OH
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I'm talking about 1 corner or diagonal corners.
Adding air the same in both tires will change the weight but doesn't typically change the "wedge".
09-23-2012, 11:05 PM
#83
Drifting
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At Roebling (clockwise), I run a couple of extra pounds of air in the left front and left rear to help with all of the sweeping, right-hand turns. ...................................
At Charlotte (counterclockwise), I run more psi in the right side tires. Again, very little of that has to do with tire shoulder rollover.
-Kevin
At Charlotte (counterclockwise), I run more psi in the right side tires. Again, very little of that has to do with tire shoulder rollover.
-Kevin
Wedge would be affect with changes to the left front and right rear or right front and left rear air pressures..
09-24-2012, 12:59 AM
#84
Le Mans Master
I did a lot of thinking about this while I was on the plane this weekend and here's what I came up with (I'll probably do a crappy job of explaining it).
I still say making wedge adjustments is best done with the spring(s) and not the sway bar. The sway bar is really a torsion bar since it ties together both sides of the suspension so obviously when one side is doing something, so is the other. While the same can be said of transverse leaf springs, the effect (crosstalk) isn't nearly the same as a sway bar. What you have to remember is that the bar itself has a spring rate, but it's mounted inside squishy rubber bushings so actually calculating the effective spring rate at the wheel would be nearly impossible.
I guess what I'm trying to say is that the job of the sway bar is to control the weight shift, not to skew corner weight numbers sitting still on a scale pad. Let's say you disconnect all the bars and set the corner weights to 50%. Then you install a small OEM C5Z rear bar and preload the crap out of it to make the crossweight change to 48%. My gut tells me that the car isn't going to behave the same as it would if you set the cross to 48% to begin with and then adjust the bar to zero preload. It would probably be easier to test all this on a stock car that only turns left, but that's not what we're doing.
I still say making wedge adjustments is best done with the spring(s) and not the sway bar. The sway bar is really a torsion bar since it ties together both sides of the suspension so obviously when one side is doing something, so is the other. While the same can be said of transverse leaf springs, the effect (crosstalk) isn't nearly the same as a sway bar. What you have to remember is that the bar itself has a spring rate, but it's mounted inside squishy rubber bushings so actually calculating the effective spring rate at the wheel would be nearly impossible.
I guess what I'm trying to say is that the job of the sway bar is to control the weight shift, not to skew corner weight numbers sitting still on a scale pad. Let's say you disconnect all the bars and set the corner weights to 50%. Then you install a small OEM C5Z rear bar and preload the crap out of it to make the crossweight change to 48%. My gut tells me that the car isn't going to behave the same as it would if you set the cross to 48% to begin with and then adjust the bar to zero preload. It would probably be easier to test all this on a stock car that only turns left, but that's not what we're doing.
