i didnt measure this myself, but borden did:
before: In stock form, the FFR gets some toe-in when the wheel is turned
approx 20 degrees. About .25"
after: With the change, I measured approx .3 inch of toe-out at approx 20
degrees of steering input. Thats about .5 inch of toe change from before and
after the change.
he said he has been consistently 0.5 seconds faster since the change. i
drove the car both before and after, although the damn thing has so much
power i cant breathe, much less notice anything thats happening.
what is the toe-out change on, say, a miata?
i thought the ackermann measured the the amount of toe change with steering
deflection. 100% ackermann allows steering with 0 slip angle of both front
wheels. right? wrong?
-james
----- Original Message -----
From: "Barry Spencer" <bspencer@tsoft.com>
To: "James Creasy" <james@thevenom.net>; <ba-autox@autox.team.net>
Sent: Wednesday, January 08, 2003 12:28 PM
Subject: Re: ackermann tuning for autox?
> Hi James,
>
> Ackerman and toe-out on turns are two seperate things. Changing the rack
> position won't change the ackerman, but it will change the toe-out on
turns.
> On custom made/kit cars you need to measure the toe-out on turns, for
> example if you turn your steering wheel half a turn on an average autox
> course, measure what toe-out on turns you have at that point, don't forget
> to add your static toe setting to that amount. Let me know what that
> measurment is and let's go from there.
>
> Thanks
>
> Barry
>
>
>
> ----- Original Message -----
> From: "James Creasy" <james@thevenom.net>
> To: <ba-autox@autox.team.net>
> Sent: Wednesday, January 08, 2003 11:11 AM
> Subject: ackermann tuning for autox?
>
>
> > i know ive asked this before, but here i am again...
> >
> > i am right in the middle of changing the position of my steering rack to
> put
> > more ackermann in my car. i think it changes it from about -100%
> ackermann
> > to +30%. however ive got no clear idea of how to determine how much i
> > should have. i know it has been debated for years, but modern tire
> > composition might warrant higher amounts of it.
> >
> > will anyone else that has set up this give me any hints? what should i
> look
> > for in tire temps, etc. (this is with dot-r tires. )
> >
> > the bonus question is what about my car might make it have an unusual
> > affinity for hoosiers- a good two seconds faster than on kumhos (on
> > concrete). or are kumhos just that much worse on concrete but not so
> > different on asphalt?
> >
> > thanks,
> >
> > -james
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