but ackermann WORKS *because* it changes the front toe-out on turns? or am
i hopelessly confused? isnt the method to make the two front wheels
describe two different sized arcs completely defined by the additional
toe-out?
-james
----- Original Message -----
From: "Barry Spencer" <bspencer@tsoft.com>
To: "Charles Cox" <charles@coastalbay.com>; "ba-autox"
<ba-autox@autox.team.net>
Cc: <james@thevenom.net>
Sent: Wednesday, January 08, 2003 2:48 PM
Subject: Re: Ackerman
> Charles,
>
> The Ackerman is measured through the center of the TRE and the king pin
and
> then both those lines meet somewhere close to the center of the diff,
> depending what % of Ackerman the car has. Changing the rack position
doesn't
> change those lines so the Ackerman stays the same, but it does change the
> toe-out on turns.
>
> Thanks
>
> Barry Spencer - Owner
> Spencer's Motorsports
>
>
>
>
>
>
> ----- Original Message -----
> From: "Charles Cox" <charles@coastalbay.com>
> To: "ba-autox" <ba-autox@autox.team.net>
> Cc: <james@thevenom.net>
> Sent: Wednesday, January 08, 2003 2:15 PM
> Subject: Ackerman
>
>
> > Actually moving the rack will change the Ackerman as will toe and other
> > alignment changes. They are two separate things but are inter-related.
If
> it
> > could be done, properly setup Ackerman steering would align the king-pin
> > centerline with the steering arm to tie-rod end connection with the
> > centerline of the rear axle. Unfortunately, there are many variables
that
> > change this effect some of which include king pin angle, height and
> location
> > of steering rack, height and angle of steering arm, etc. You also need
to
> > consider bump-steer, roll-steer, roll-couple among other things.
> >
> > Charles
> > mailto:charles@coastalbay.com
> >
> >
> > ----- 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
> >
> >
> >
> > > 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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