The way tire preassure works is that for one day with set conditions
(weather and track) there is one tire preassure that will yeild optimum
traction. Low preassure will yeild more tire rollover and a mushy feeling;
high pressure will yeild less rollover and a hard feeling but both will
create less than optimum grip. when underinflated the center of the tire
starts to lift off the ground and traction comes from the sides of the
contact patch, when over inflated the sides begin to lift off and traction
comes from the center of the contact patch. both configurations will
yeild less overall traction, but they will do it with different 'feel'.
Typically you don't feel an overinflated tire because it seems solid right
up until the limit of adhesion. You will feel an underinflated tire
because it starts feeling mushy.
So far everyones descriptions of over/understeer have been acurate.
Oversteer = rear end slides out
Understeer = front end pushes straight when wheels are turned
James Nazarian
'71 B roadster
'71 BGT ever so slowly turning into a V8
'63 Buick 215
"I sure wish I had a racer's budget, or are the racers just better at
explaining expenses to the wife?"
-Unknown
On Tue, 22 Aug 2000, Max Heim wrote:
> No, your description is correct AFAIK... curious. I have found that I
> experience this effect if my rear tire pressures are too low. And I would
> think that higher rear pressures would result in more rear grip, not less.
>
> The information I referred to is from the Moss catalog, presumably
> written by Lawrie. Perhaps he could explain the theory. Again, this is
> only applicable to a more or less stock chassis setup.
>
>
> ATWEDITOR@aol.com had this to say:
>
> >In a message dated 8/21/00 5:44:46 PM, mvheim@studiolimage.com writes:
> >
> >>1) I believe that recommended tire inflation for B roadsters, at least,
> >>is 3lbs. greater at the back than the front...
> >>
> >>2) ...and the reason for this is to AVOID oversteer; therefore, if I
> >>understand this correctly, your setting of 30f/35r would actually induce
> >>mild understeer. Conversely, the 25/25 setup should induce mild oversteer
> >>-- and in my experience, actually does.
>
> >Maybe I've confused the terms. The effect I'm talking about is when you can
> >get the rear end to break loose somewhat in a turn. I've thought that was
> >"oversteer." Wrong? In any case, having stiffer rear tires (higher
> >pressure) with less flexing in the sidewalls surely is the way to get that
> >racy feeling of drifting through a turn, wheel turned slightly against the
> >turn to maintain direction. Ah! Can't beat that.
> >
> >Jay Donoghue
> >72B
> >72B-GT
> >66Mustang
> >
>
>
> --
>
> Max Heim
> '66 MGB GHN3L76149
> If you're near Mountain View, CA,
> it's the red one with the silver bootlid.
>
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