Hi Kim, Gordon, all
The theory is that psi measured hot is what counts. On a cold and wet day
(say 40F) (I dont know about sub zero) I have used as low as 20 - 23 psi
(measured cold) for short races with really good results, but as Gordon
says ONLY with R series tires. Don were you talking hot or cold
measurements (34 38 seems high for cold)?
With the non independent suspension on the rear, tires form a more
important part of the suspension and using 3 or 4 psi less in the rear will
improve ride and give better handling even in racing conditions. When we
used to race with normal radial tires on my 2000 with 185/60 14's (2 years
ago), I was using about 33 to 36psi (lower for lower air temp , measured
cold) in the front and always 3 or so less than that in the rears. This was
verified with a pyrometer, in race success and in tyre wear.
On camber, check how your tires wear for road use, if they scrub the
outside and everything else is OK (balance, alignment), then try a bit
more -ve camber than 1deg.
If you are racing go to at least 2.5 deg neg.
Regards,
Howard (I have 3 of those solex things, race one of them)
-----Original Message-----
From: Gordon Glasgow [SMTP:glasgow@serv.net]
Sent: Saturday, 12 February 2000 4:05
To: datsun-roadsters@autox.team.net
Subject: Re: Tire Pressure
I'd agree with Don Miller on this. It does depend on your tires and your
driving style. Assuming you are using "merely" high-performance street
tires and not R-compound stickies, I'd start at 38 all around and go
from there. If it's understeering a lot, drop the rear pressure about 2
psi at a time. But don't go under 30 psi unless you have R-compound
tires that are designed for that low of a pressure. If you have access
to a pyrometer, check it that way.
2 degrees neg camber will work great at an autocross but may be a bit
squirrely on the street. If you are only going to autocross
occasionally, I'd stick with about 1 degree negative.
KWS711@aol.com wrote:
> Can anyone out there reccommend a good starting point
> for tire pressure for auto-x. I'll be running 185-60-14's with
> comp front springs & swaybar. Also any thoughts on
> front end adjustments (camber, caster, etc.)
>
> Thanks
>
> Kim
> 68 2000 CSP
--
Gordon Glasgow
http://www.gordon-glasgow.org
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