DETERMINING YOUR PROPER TIRE PRESSURE FOR HANDLING

Tire pressure has a profound effect on your cars handling ability. Acura's
pressure recommendations are geared towards stock tires, and a balance between
handling and ride quality. If you want to achieve the maximum handling ability
on your tires, you have to deviate from acura's recommendations. With the extra
handling comes a sacrifice, often tire wear and ride quality. For performance
enthusiasts, and AutoX/Track events, that sacrifice is a small one for the grip
and handling that proper pressure provides.

Finding your optimal tire pressure requires:
1) access to air
2) a place where you can abuse your tires
3) An accurate tire gauge
4) a bottle of shoe polish

For air, most gas stations provide air for free, or you can find an electronic
air pump that plugs into your cigarette adapter. For shoe polish, pick
up a bottle of liquid white shoe polish with a sponge tip. Finding a good
place to really work your tires is often the hardest part. Just some suggestions,
you could getting permission from an owner of a big parking lot, maybe
your boss will let you use the company parking lot after hours, one of
the most common places to tweak your tire pressure is an AutoX/Track event.



What PSI you should start off with depends from tire to tire, but since its
easier to remove air than add it, I recommend you start fairly high. I started
with 5psi below the rated maximum, in my case that's 40psi.
Start off by driving your car around for awhile, to heat up the tires.
As the air inside of the tires heats up, it will expand and the pressure
will increase.
Make three-four marks on all of your tires with the shoe polish. Each
mark should run from the last block of tread and run down over the shoulder
of your tire and onto the sidewall.


Now you are at the fun part, putting stress on your tires. It
is very important that you do this safely, and legally. Tire pressure isn't
going to do you any good if you wreck your car or get your license suspended.
Start doing some heavy turning, and really your tires squealing. If you don't
go fast enough you probably won't rub off any shoe polish. You want to create
the maximum load possible on the sidewall of your tires (when the sidewall is
going to flex the most). After abusing your tires for awhile, stop and take
a look at the shoe polish marks. If the scuff is still on the edge of the tread,
you have to much air pressure. If the shoe polish has been rubbed off on the
sidewall and past the edge of the tread you need to increase the air pressure.



Make adjustments in 2 PSI increments, until you find your optimal tire pressure
for all four tires. After you have changed the pressure, make the marks again
and do another abusive run after a short break. Make sure to let your tires
cool down a bit, as street tires get hotter their grip diminishes.
Once you have found the optimal PSI for all the tires, make a note of it for
future reference. What you will end up with, is the largest contact point with
out driving on the sidewall of your tires. A general rule of thumb, is the larger
the contact point the more grip you have. By lowering the PSI the tire has,
the more it will sag at the bottom creating a larger contact point. Of course
there is a limit, once you start driving on the sidewall your grip will be severely
effected because the opposite side of the tread will get lifted into the air.