Who’s Running A Kussmaul Setup?
12-13-2010, 02:37 PM
#31
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A minute is equal to one sixtieth (1/60) of one degree.
Porsche uses minutes of angle in the workshop manual.
The other way is to use decimal of a degree so
with minutes when you say 1.30 degrees that is 1.5 degree.. these two are equal.
Your target is to get at least 30 minutes total toe at the rear which means 15/60min per side or 0.25/100 degrees per side or 0.5 degrees total.
Note : Toe also can be measured in millimeters or inches if you know the wheel / tyre diameter : )
You don’t want less toe in the rear because with stock suspension accelerating and braking will cause the rear of the car to become nervous from the toe changes (car toes out)
If your suspension if very firm and most rubber has been removed from the rear you can play with less rear toe because the kinematic toe changes from loading or unloading the rear suspension are less dramatic.
Porsche uses minutes of angle in the workshop manual.
The other way is to use decimal of a degree so
with minutes when you say 1.30 degrees that is 1.5 degree.. these two are equal.
Your target is to get at least 30 minutes total toe at the rear which means 15/60min per side or 0.25/100 degrees per side or 0.5 degrees total.
Note : Toe also can be measured in millimeters or inches if you know the wheel / tyre diameter : )
You don’t want less toe in the rear because with stock suspension accelerating and braking will cause the rear of the car to become nervous from the toe changes (car toes out)
If your suspension if very firm and most rubber has been removed from the rear you can play with less rear toe because the kinematic toe changes from loading or unloading the rear suspension are less dramatic.
12-13-2010, 03:20 PM
#32
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i'm shimmed 11mm or so for -3.2 camber and have slight rubbing on the plastic liner, not too bad tho, only at full lock, very minor under lots of compression on the track (really tight corners)
my shop recommended only shimming, no strut rotating. he told me he wanted to maximize the caster as much as possible. i listened, he's greg fordahl afterall
http://www.alexjobracing.com/team_fordahl.htm
i'm no expert but i do know one thing, the car handles beautifully, its a dream to drive on track except when the rear toe goes out of wack then its scary! adj toe links solved that problem. anyway, love the turn in, handling on track, everything is dialed. running nitto nt01 tires 245/315.
my shop recommended only shimming, no strut rotating. he told me he wanted to maximize the caster as much as possible. i listened, he's greg fordahl afterall
http://www.alexjobracing.com/team_fordahl.htmi'm no expert but i do know one thing, the car handles beautifully, its a dream to drive on track except when the rear toe goes out of wack then its scary! adj toe links solved that problem. anyway, love the turn in, handling on track, everything is dialed. running nitto nt01 tires 245/315.
Since caster is not adjustable by itself, I think the only way to tell the difference that caster makes (other than fender liner rubbing) would be to A-B higher and lower caster (i.e shims versus struts rotated) at the same fr camber setting and see which feels better to you. Not sure any of us have actually done that....so just take the best advice of your local setup guru.
12-13-2010, 03:39 PM
#33
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With about -2.5 to -2.6 deg up front I was cording the front outside shoulder of my R6. I'm now at -3.0 deg up front and I'll see how the tire temps and wear are next season.
12-17-2010, 03:45 PM
#34
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Tarret goodies arrived today. I've decided to let a professional shop help me with these tweaks. Instead of the TRG rear shock mounts, I'll run the PMNA pieces.
12-17-2010, 04:24 PM
#37
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12-17-2010, 05:01 PM
#39
Once you've done with your settings, it could be a idea to take notes on:
- how you experience the car in different types of corners.
- measure the temp inner/middle/outside of each tire.
- look how each tire is worn.
Speak with your instructor if you get odd results because of driving style (to slow on corner entry, to late on gas on exit or whatever it might be..?). You might need to polish some detail skills.
Then bring these notes to your alignment guy and give him some feedback.
After that, you should be pretty much set.
- how you experience the car in different types of corners.
- measure the temp inner/middle/outside of each tire.
- look how each tire is worn.
Speak with your instructor if you get odd results because of driving style (to slow on corner entry, to late on gas on exit or whatever it might be..?). You might need to polish some detail skills.
Then bring these notes to your alignment guy and give him some feedback.
After that, you should be pretty much set.
