I was giving nothing to the aspect of camber. As this is separate from the
steerable geometry.
If the inner wheel does not point in the direction demanded by the
turning radius and tire slip angle generated by it's loading, then it must not
be running at it's most efficient condition. Drag may not be a good thing.
After slowing for the corner entry, I like to get on the gas and accelerate.
Anti Ackerman geometry would be indicated to achieve the conditions that go
along with todays tires.
As a note, Ackerman geometry is determined by physical layout of the
chassis, and remains unchanged whether the car is moving or not (generating
slip angles). As mentioned, the inner wheel would describe a smaller radius
than the outer wheel. The center of radius would intersect a line drawn thru
the rear axle.
Any others interested in handling care to comment?
I took the 1600 out for a short spin last nite. A broken ballast resistor put
everything on hold. Dark and rainy!
I cannot believe how these cars just seem to need every detail attended to. I
thought I had a gift, I got yoked!
It still is fun!
Regards
Calvin Grandy
----------
> From: Howard Fletcher <hgf@netro.com.au>
> To: 'Toby B' <toby@wolfenet.com>; a roadster list
><datsun-roadsters@autox.team.net>
> Subject: RE: front end geometry
> Date: Tuesday, November 09, 1999 4:13 AM
>
> Thanks Guys , what a good read.
>
> I think I have followed the argument but feel free to correct me.
>
> On a race set up we use a fairy high number for -ve camber and stiffer
> springs.
>
> This gives us a much lesser (slip angle?) I mean the outside tire is far
> more upright during heavy conrnering.
>
> however straight line breaking does suffer a little as there is more force
> on the inside of the tire. In the wet there is less body roll so the -ve
> camber is less effective (with High -ve camber).
>
> The importance seems to be with the outside tire for circuit racing as if I
> slightly error on the apex and take in a little of the ripple strip with
> the inside front wheel , it has very little effect on the attitude of the
> car. (We dont have any banked tracks).
>
> The ackerman angle seems only to have importance in the inception of the
> turn (less so if you are under brakes and turning) and perhaps the late
> part of the exit as it is in thse spots that both frnt wheels are doing a
> lot. In the rest of the turn it is the job of the outside tire. Most
> racing schools seem to emphasise that effect in looking at steering under
> breaking.
>
> Regards,
>
> Howard
>
>
> > Has anyone modified the front steering system to provide anti-Ackerman
> geometry as is consistent with present day tire performance?
>
> The stock design does have Ackerman-angle compensation built in.
> Hmmm... if the slip angle goes up on both tires (theory being that
> modern tires have greater operating slip angles) would that change the
> Ackerman angle much? Wouldn't seem to...
> (Ackerman angle is the technical term for "inside tire has to turn into
> a corner more as it's radius around the turning point is smaller than
> that of the outside tire')
>
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