Re: Tires for GTV6

[Chris.Prael@xxxxxxxxxxx (Chris Prael)]

The last time Road and Track did a tire comparison test, the best wet second
best dry tire was the Dunlop D40M2.  At the time, Dunlop also claimed that the
tire outperformed the top-of-the-line Goodyears on a 'Vette.  When I bought
them for $108/corner for the correct size for a GTV6 (205-55/15) they were a
very good value.  Their performance in the wet was excellent and they stick to
the limits of the front suspension geometry in the dry.  They lasted 32,000 
miles, which is extraordinary for an ultrapreformance tire.  They are now
priced at only $80/corner.

When they wore out, I upgraded to SP8000 tires at the same price that the
D40M2s first cost me.  As advertised, they are even better than the D40M2.

For those who are curious about the geometric limitation on cornering speeds,
they fron geometry of the GTV6 keeps the outside tire perpendicular to the
pavement through approximately 15 degrees of body roll.  With greater roll,
the outside front wheel camber goes positive, quite rapidly.  By leaning off
of verticle, the size of the contact patch shrinks which excedes the sheer
strength of the rubber causing the front wheels to slide.  Classic,
designed-in geometric understeer.


Anyway, the Dunlops are far and away the best value in ultra performance tires
in the US market unless you are autocrossing or doing time trials.

Chris Prael

> Date: Fri, 18 Sep 1998 17:01:49 -0700 (PDT)
> From: Jess Liao <jessl@domain.elided>
> Subject: Re: Tires for GTV6
> 
> Bruce Murray wants tires that's good in wet yet performs.
> Richard replied:
> > i always found Yokohama A509s to be a very good wet/dry tire for my 2.5L
> > milano. the Yoko AVSi is a better dry tire, but not quite as good in the
> > wet (still not bad, though.)
> 
> I totally agree with richard here about his comments on both tires!!!
> The truth was that I used to run A509 in snow when I lived in Iowa!
> 
> Both A509 and AVS-i are very good in wet. The AVS-i, though often said to be
> "not quote as good in wet", is already better than many of the so-called
> all weather tires! 
> 
> A509 is really cheap for what you get out of it. 
> 
> Jess
> BTW, worn A509 works well in wet with predictable handling.

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