[s-cars] Snow tire shopping, blizzak vs Nokian vs? thoughts?

[JC]

Agree completely w/ Larry - go easy on the extra inflation - I think I
usually run 4-6 psi more, but certainly not looking to fill to max. spec.  
 
Re: tire pressure and steering I agree about the specific effects on the
front, but disagree or perhaps some additional clarification on
over/understeer - In most OEM cases you WILL see decreased understeer as the
front tightens up while the rear of the car continues to pivot out a bit
more on the softer tire pressures.  The limitation is (maybe this is what
your'e saying?), if rear is very firm already, then the phenomenon may not
occur to a noticeable degree, and in fact if you go too far you'll start to
see the trend reverse as the front grip starts to decline again under
overpressure.  However *at most 'OEM sticker' pressure starting points* if
you pump up the fronts, while leaving the rears the same (or increasing to a
lesser degree) the result will be less push. 
 
 
---- current ----
1995.5 S6 Avant 
---- past lives ----
2006 A4 2.0TQA
1998 A6Q 2.8 PES G2
1989 200TQA SJM
1990 CQ
1997 A4 1.8TQ Wett
1987 4kCSQ 
 
John J. Cunningham
 <mailto:jc at j2c3.com> jc at j2c3.com
US Mobile +1 (617) 750-5025
Main / Global +1 (978) 633-3510
China Mobile: +86 (0) 136 6080 9560
 


  _____  

From: LL - NY [mailto:larrycleung at gmail.com] 
Sent: Monday, November 17, 2008 23:32 PM
To: Mark Turczyn
Cc: JC; Calvin Craig; Scar
Subject: Re: [s-cars] Snow tire shopping, blizzak vs Nokian vs? thoughts?


Don't go crazy with the pressures (see November 2008 Grassroots Motorsports
Magazine for a skidpad test) until you see what the results are. The common
suggestion is to change pressures 2 psi at a time until you arrive at the
happy medium (in your case, even wear) that you are desiring. 

FWIW, higher front pressures (assuming adequate pressure to begin with)
don't actually reduce understeer, they just improve response (at the
potential expense of ride quality (which was Audi's concern) and potential
center wearing of the tires) and predictability, which IMHO are the most
important factors in street driving over ultimate grip. Of course even wear
is also important. A side benefit of higher pressures is (slightly) improved
fuel economy.