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  blueILLUSION97

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  daytrader

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My boxster has stock suspention and here is alignment im going for to use on street driving and auto-x what do you guys think of this....

Front: Camber (maximum possible probably) -0.7
Toe 0

Rear: Camber (maximum font plus -0.5 probably) -1.2
Toe total combined 1/8"

For your front camber your going to want a full degree of negative camber, You dont want your rear to have alot more camber than the front because you will understeer alot. You want it close to the same spec as the rear camber

Well i dont know what 1/8'' for toe is but the threshold is 0.00 to 0.17 degrees... Here some schooling on the rear toe does...

Rear wheel toe positive: As the toe is adjusted progressively more positive, in cornering this will cause the rear of the car to come around a curve in almost a swing effect.... almost similar to a car with rear wheel steering, ie: 90-96 300zx.

Keep in mind, the further positive the setting is placed out of spec, tire wear will result as well as unwanted wiggling of the rear end when going over bumps.

I dont know what negative toe does but i dont think it matters since the minimum toe recommended is 0.00

  aren040

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  blueILLUSION97

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  aren040

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Yeah half a degree will make a difference since the rear wheel are also wider than the fronts which by itself also adds to the understeer. If anything, you want the rear wheels to break free first and never the front... Remember neg camber wont really wear your tires down... its Excessive toe that grinds them away!

  aren040

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  blueILLUSION97

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Yes having too much toe out will cause understeer but so will having too little neg camber in the front compaired to the rear wheels. You dont really want to rely on toe out to cure your understeer problem cause it will devour your tires FAST! lol Use Camber, Too much toe-out will make your car pretty unstable over bumps and will annoy the crap out of you... cause teh rear end will wiggle left to right sharpy when you go over bumps.

  aren040

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  blueILLUSION97

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  blueILLUSION97

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That person who replied isnt accounting for the increase in camber that the rear wheels will get in cornering as well which means you still have far less grip in the front than the rear. So that doesnt mean you dont still have to increase the camber in the front... Its not only the fronts that this happens too... regardless you need more camber.


FYI, Caster cannot be adjusted unless you have Aftermarket upper control arms like I do.

  aren040

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  blueILLUSION97

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Caster used to be able to be adjusted on the older 911s if I remember correctly. I think for the 996/986 they removed it, so up to 993 I think Porsche allowed you to adjust it from the factory.

Also, keep in mind that the TOE out in the rear under acceleration will help you when you have to push the go pedal in mid turn. It should help you keep the rear in check. Unless I am missing something here, CJ am I correct in my thinking.

-aren

Im not sure weather that is a charactoristic of toe out but i do know that toe out will increase oversteer in a turn because in a turn, the rear wheel with all the weight on it will be pointing outwards due to the Negative Toe, thus pulling the rear end out of the turn.


Toe in will increase understeer because in a turn, the rear wheel with the most weight on it will be pointing inward into the direction of the turn thus increasing rear wheel grip.

How can it happen to the rear as much as it happens to the front? From my understanding you get that extra camber because the wheel is turned by steering input.

Thats true, but you still get an increase in rear wheel camber from turning and plus the weight of the engine and trans are on the rear wheels, havent you ever noticed that the boxsters rear end squats alot during acceleration and turning?

  blueILLUSION97

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