are you referring to 100% ackermann? ive not seen that recommended for race
or street cars.
bump steer will be retuned after the change of course.
roll steer: is there significant roll steer in double a-arm setups? i hadnt
considered this. my suspension roll is limited to 2 degrees at 1.4 g's,
which is the range where i thought my geometry is well behaved (front and
rear double a-arm). anyway im not planning to pursue this until other
projects are completed.
roll-couple how does the toe affect the front/rear roll resistance and steer
characteristic? i suspect it may affect the corner weights. does it change
the track slightly and thus the roll couple?
the usual way to adjust ackermann is the spindle design... which may be a
longer term project. it just turns out to be pretty easy to mount the rack
to the x-member.
my first goal is to reduce the amount of toe-in when i turn and hopefully
the awful power-on push i have.
thanks,
-james
----- 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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