Date:         Tue, 23 Mar 2004 21:07:32 +1200
Reply-To:     Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Subject:      Re: Better handling in windy conditions?
In-Reply-To:  <002201c41009$926725c0$e2eefea9@oemcomputer>
Content-type: text/plain; format=flowed; charset=us-ascii

>  > This doesn't show the "unsafety" of the truck tires, it shows the
>>  "unsafety" of the mechanic who installed mismatched tires. Different
>  > tread patterns and compounds can make any  vehicle unsafe.

Yeah, now I'll have to look for some car tires for the back.

>  > Stock-rated tires give a good combination of ride and handling at a
>>  reasonable price. This is a monstrous improvement over the too-common
>>  configuration in which the P.O. has replaced the stock tires with a
>>  discount P195/75R14 or equivalent single-ply sidewall tire rated for
>>  1220 lbs.
>>
>>  Messing with rim and sidewall configurations can possibly result in
>>  modest gains but most people would suffer more from the dent in the
>>  wallet than they benefit from the improvement over returning to stock
>  > spec.

Truck tires are made very much to a lowest-common-denominator price.
They are designed to carry a load and to give a basic minimum amount
of grip... and are not designed at all with cornering in mind. Want a
van that really handles? Only car tires will allow that. GOOD car
tires. Low-profile tires of necessity have stiff sidewalls, which
cuts sidewall flex and the resultant tire squirm in corners. So the
vehicle is far more stable in cornering and direction-changes.
Absolute grip is far better too, for cornering and braking.

>Not tread patterns but different compounds make a world of different.

Performance tires tend to be softer compounds. This does not
necessarily mean faster wear. Some harder tires, when pushed hard,
soften and begin to wear extremely rapidly (I destroyed a Dunlop K300
on my CBX in half an hour on a racetrack... it went off, becoming
slippery and balling-up the tread. The tire never recovered).

Mixing tire structural types can cause problems too. I rented a Mazda
Familia in Fiji... it had a real handling problem. When I looked, I
found one of the front tires was a CROSSPLY. Nasty.

Having said that, the most dramatic handling improvement I've ever
experienced was by mixing tire types when I was a poor student with
my 57 Split panelvan. It had crossplies all round... so I found some
used radials off a Jag. Put them on the back. These transformed the
handling... no more rear-end slides.

Always remember that in an emergency avoidance maneuver p[erformance
tires can easily make the difference between hitting the obstacle and
missing (or missing it and having your own nasty accident off to the
side in the shrubbery) it entirely. Skimping on tires has no doubt
cost a lot of people their lives.
--
Andrew Grebneff
Dunedin
New Zealand
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut