rec.autos.simulators

Also: minimum camber thrust.

Ahhhhhhh, the good old days of speed records at the Smogbank... that is,
until everything started again with the Honda/Brabham chassis :-)

--
-- Fran?ois Mnard <ymenard>
-- http://ymenard.cjb.net/
-- This announcement is brought to you by the Shimago-Dominguez
Corporation - helping America into the New World...

2 schools of thought:

Run a lot of camber and very high TPs and ride on the inner edge of the
tire, or

Run 0 dynamic camber and very high TPs and ride on the center of the tread.

I prefer the latter.

*does* affect the Vmax, but plenty of people disagree.

Honda/Brabham chassis :-)

...which has been a helluva fun, too. ;-)

Regards
Crash

What do you consider a lot?  I generally don't use more than 0.125 in.,
but I have seen certain Finnish people using as much as 0.3 in.  At what
point do you really start to lose top speed?

The Q was in re Vmax, not lat. acc..

Haq,

You're a stand-up guy; try the test yerself.  I used Kya, but I suppose a
better test would be Le Mans or Reims (neither were avail when I did this,
altho Avus was - I just didn't care for it).  Nothing much happened until
you got abt. .125-in. into the pgm.  I tried it all the way up to .500 in.
(which is what some enduro cars were using in the 70s & 80s, in front, neg.,
with spool axles, to try to counter the u'steer).  Splayed like that, I was
losing 3-5 mph off the top end.

--Steve

Well since I have not yet found the need for more than 0.125 toe out in
front or 0.125 toe in at the rear I see no reason not to just believe
you.  Okay the real reason is it's the holidays and I'm feeling lazy.
Anyway, why should I doubt you, you wrote the freaking book!  ;o)  Oh
well, maybe when I get a little more time and energy I will try some
testing at Spa.  If it shows up anywhere, it ought to show up there.

F3's have different tire characteristics though, don't they?  Plus I
would think you would get nowhere near the same top speed with an F3.
Oh well, almost every time I have gone past 0.125 the handling gets too
unstable for me anyway, so as long as there is no penalty for 0.125 I
guess I don't need to be concerned.

Mmmmm, I don't think Spa is The Test.  Going down the hill, well, it's
downhill.  And going up the hill, well....  Ditto Riverside (at least going
down the back stretch).  I'd try Reims or Le Mans.

You can run flat out at Tally all day...but not at the Vmax, which takes a
longer to achieve than the stretch between T2 & T3.

Actually if we really wanted to prove this out the right way to do it is
not with a top speed test but with a coast down test.  Top speed tests
won't be reliable if you don't change the gearing, plus they are
influenced by how well you came out of the previous corner, or in the
case of Kyalami, how well the car handles through the kink.  A coast
down test would get rid of these variables.  You would need a track with
a long flat straight, like Monza perhaps.  Accelerate up to the
start/finish line, then cut the throttle and put the clutch in (to
eliminate the engine braking effect) and let it coast down to zero.  To
be accurate you would have to analyze this in GPLRA or something
similar, so the person should then start the car up and complete the lap
so that the replay can be loaded into GPLRA.  Then in GPLRA in the speed
vs. distance graph pick out the time it takes to coast from one speed to
another.  The longer the time, the less the rolling resistance.  You
would have to pick an initial speed that is less than your s/f speed in
order to be consistent, say 150 mph.  Or go even lower to reduce the
influence of aero and increase the resolution.  Also you would not want
to time it all the way to zero, again for consistency.  For example
compare the time it takes to go from 60 mph down to 10 mph.  I don't
know whether the replays really have enough resolution to be able to see
the differences that we are talking about, but ideally this is the best
way to sort out differences in rollling resistance from one setup to
another.  Maybe someone else with a little time on their hands can try
this out.