Alignment questions

[Adam]

Originally Posted by demick

Max camber I was able to get with a stock '04S suspension was -0.8deg. Doesn't seem that -1.5deg is in the realm of possibility unless the suspension is modified, or unless lowering the car adds neg camber (I'm not sure if it does or not).

Demick, did they mention how much rear camber was possible? Thanks!

[demick]

Demick, did they mention how much rear camber was possible? Thanks

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I did my own alignment. I was only trying to increase front camber. I measured rear, but didn't want to increase it for tire wear reasons (I forget off the top of my head what the measurement was, but I'd guess around -1.5deg). So I don't know what the max is. I'd be hesitant to go more than -2 to -2.5 deg on a street car.

Was was really interesting, is after setting the front camber to max (-0.8deg), the toe changed drastically (gave me about 1.2" of toe out!!). I expected the toe change, just not nearly that much. Needless to say, I reset the toe to zero, but not after driving 40 freeway miles and competeting in an autox. Craziest thing is that the handling on the freeway wasn't half bad with that huge amount of toe out. Go figure.

[Adam]

Originally Posted by demick

Demick, did they mention how much rear camber was possible? Thanks

<\quote>


I did my own alignment. I was only trying to increase front camber. I measured rear, but didn't want to increase it for tire wear reasons (I forget off the top of my head what the measurement was, but I'd guess around -1.5deg). So I don't know what the max is. I'd be hesitant to go more than -2 to -2.5 deg on a street car.

Was was really interesting, is after setting the front camber to max (-0.8deg), the toe changed drastically (gave me about 1.2" of toe out!!). I expected the toe change, just not nearly that much. Needless to say, I reset the toe to zero, but not after driving 40 freeway miles and competeting in an autox. Craziest thing is that the handling on the freeway wasn't half bad with that huge amount of toe out. Go figure.

Interesting, with that much toe it should've been all over the place. Do you have any ideas why Porsche would dial in - camber in the rear, but not the front from the factory?

[demick]

Originally Posted by Adam

Interesting, with that much toe it should've been all over the place. Do you have any ideas why Porsche would dial in - camber in the rear, but not the front from the factory?

Front wheels generally don't need as much neg camber as rears, because they have caster. With caster, when you turn the front wheel, the wheels lean into the direction you are turning - essentially giving you neg camber on the outside wheel and pos camber on the inside wheel. Exactly what you want when you turn. The rear doesn't have this, so it has to be built-in.

[Adam]

Originally Posted by demick

Front wheels generally don't need as much neg camber as rears, because they have caster. With caster, when you turn the front wheel, the wheels lean into the direction you are turning - essentially giving you neg camber on the outside wheel and pos camber on the inside wheel. Exactly what you want when you turn. The rear doesn't have this, so it has to be built-in.

Cool, thanks for the explantion. Caster is the hardest thing for me to wrap my head around. I've been researching it online trying to get a better understanding.

[demick]

Caster not only gives you added camber in whatever direction you turn like I mentioned, it is also responsible for giving stability to the steering system. When you go around a turn and let go of the steering wheel, it has a tendency to self-center. Or just going down the highway, it's why you can let go of the steering wheel and the car will continue to go straight. Both of these can be directly (although not entirely) attributed to caster.