I thought this was kinda strange advice, too. Maybe what they are trying to do
is to reduce the
traction enough that you won't be able to build up the lateral G's necessary to
roll it.
I may be biased, but I see any SUV as a rollover looking for a place to happen.
Sure, there are
exceptional drivers out there who can handle one fine. I've heard wild stories
about Bob Bondurant
taking a load of students around the track in a 9-passenger van and DRIFTING IT
through the turns,
but not everyone is a Bondurant.
svgkm@halley.ca.essd.northgrum.com wrote:
> Maybe some of the racer/gurus out there can speak more definitively on this
>subject, but
> it seems to me that softer tires would exacerbate the tendency to roll -
>based on this
> line of logic: The high CG placement of these vehicles means there is a
>longer moment arm
> between the center of mass and the tire contact patch; the large mass acting
>through this
> distance results in a large (and aptly-named) overturning moment. Any
>increase in
> flexibility in the structures (suspension, that is shocks/struts, and tires)
>that resist
> this overturning moment results in higher deflection angles; that is - greater
> displacement of the CG from center and a greater tendency to ROLL OVER!
>
> It is exactly the combination of high CG, large mass and soft suspension that
>makes SUVs
> so roof-happy, especially in avoidance maneuvers at speed, when a high rate
>steering input
> combined with the vehicle's velocity create very high forces acting against
>the cushy
> suspension systems these vehicle are typically equipped with. The sudden
>inputs required
> to correct for a blown tire are an example of what to do if you want to put
>your typical
> SUV on it's roof. If it were me, I'd crank the pressure up to reduce tire
>body heating on
> my way to the tire store to buy some Michelins...
>
> Gay McCormick
> San Jose, CA
>
> Pamela Pepoy wrote:
>
> > [snip] However,
> > Ford says to only inflate them to 30 psi (soft to avoid the Explorer's
> > inclination to tip over and roll). Firestone says to inflate them to 35
> > psi to stop them from heating up and peeling off like a bannana skin and
> > also causing the Explorer to roll. So, my NEW, SAFE family vehicle is
> > an unsafe, certified turkey.[snip]
> > Guy
> > 67.5 SPL311
> > Tempe, AZ
> >
> > --------------42B278C8638BE7302B0EB185--
--
Gordon Glasgow
http://www.gordon-glasgow.org
|