Sadly I can't find any measurement data on the old Toyota van, which also
had a common propensity to blow up and/or catch on fire, but that's another
story...
Hey Kevin! Where did you get those track & height numbers on all those
vehicles so fast?
-Carl
> ----------
> From: Derek Butts[SMTP:pnc1@earthlink.net]
> Sent: Thursday, October 19, 2000 4:07 PM
> To: Bill Hamburgen 650-617-3329 FAX -3374
> Cc: ba-autox@autox.team.net
> Subject: Re: Vehicle eligibility...
>
> In fairness to this discussion the Toyota Van I drove had 175,000 miles on
> it
> with the original shocks and crappy tires. I think it was a 1989 with the
> narrower track and higher center of gravity. The Previa is a later model
> Toyota van with a wider track and wheelbase.
>
> Sorry, my mistake - the Previa does look like a turtle, though : )
> -Derek
>
> Maybe we should institute a policy that the Safety Steward test drives the
> proposed vehicle at speed and if it rolls they simply hand back the keys
> to the
> owner and say "this vehicle is not acceptable for Solo II" : )
>
> Bill Hamburgen 650-617-3329 FAX -3374 wrote:
>
> > I'd been holding off weighing in on this, but I can't any longer.
> > Derek Butts said:
> >
> > > I have driven this van before. We used to have one as a parts van.
> > > If autocrossed it will end up like an upside down turtle....
> >
> > I have both autocrossed my Previa and been up on two wheels in my GTI.
> >
> > My Previa is an Altrak, with a rear sway bar, good shocks, and slightly
> > lower than stock due to low profile tires (215/60-15). It handles
> better
> > than a lot of sedans. I autocrossed it once at an SFR event (at Alameda
> > NAS about 4 years ago) and my time put me in the top 80% of the entire
> > field. Beat a Porsche, a Vette, and a Tiger among others. Look it up.
> >
> > My GTI was running in ES on BFG R1s at another SFR event. My co-driver
> > sawed the wheel trying to catch a spin and got us up on two wheels.
> > I couldn't tell, but Katie Elder and other reliable witnesses said they
> > saw air under the tires. I did not like this. I lowered the car 1.25",
> > beefed up sway bars and moved to DSP. The car is now totally
> > uncompetitive, but is safer and a lot more fun to drive.
> >
> > What's the point? That vehicle/tire combos that roll with some
> regularity,
> > such as race rubber clad but otherwise stock VWs, BMWs, and various
> > econoboxes, are allowed to run events, but others that *may* be even
> less
> > prone to rollover provoke a knee jerk reaction like, "A Previa is not an
> > acceptable vehicle for Solo II"
> >
> > My suggestion: you can't easily measure CG during tech, but you can
> > measure outside dimensions. CG height can be conservatively
> approximated
> > as the midpoint between ground clearance (C) and height (H). Divide the
> > estimated CG height by the track width (T) and use that ratio as a
> > stability index.
> > C + H
> > ----- = stability index
> > T
> >
> > Pick a cutoff stability index that would exclude vehicles already known
> > to have a propensity to turn turtle (VWs, 3 series BMWs, etc).
> > And encourage vehicles over that ratio be excluded by the safety steward
> > on stability grounds, unless the vehicle is classed in the rulebook.
> > Perhaps my Previa could have been excluded on under this rule. So be
> it.
> >
> > Note that lowering a vehicle reduces both C and H. This correlates well
> > with what we all know intuitively.
> >
> > I'm not claiming this formula is perfect, but I think it's better than
> > excluding vehicles based on appearance.
> >
> > /Bill
>
>
>
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