Howdy,
On Thu, 29 Apr 1999, Mark Sirota wrote:
> Assuming a car with reasonable ackerman (something close to 100%), then
> adding static toe-out causes the inside front tire to turn too far.
> This creates some drag around the inside front tire, which causes the
> car to want to rotate around the inside front tire -- hence, quicker
> turn in.
>
> I have no idea if this is a real effect, or if it's more or less
> significant than the bushing preload that Mark mentions, but it makes
> sense to me.
>
> Note that real race cars don't have rubber bushings and therefore should
> get very little preload, but toe adjustments do affect turn-in.
That makes a lot of sense. I agree that I dunno to what degree it would
affect things, but it would account for both the turn-in improvement and a
mid-corner understeer (since the inside front tire is now turned too far).
The only fly in the ointment would be that it shouldn't matter if the
above car is running toe out or in. In either case the inside front tire
would have extra drag (give the outside front tire tracking straight due
to weight transfer). Perhaps the desire of a toed-in car's inside wheel
to go straight rather than turn more would simply overcome the minor drag
however...
Either way, that's a pretty good idea! Wouldn't it be cool if we all had
jobs where we could instrument our cars and test this stuff?
Mark
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