Contour Enthusiasts Group Archives Forums Modifications Wheels & Tires Auto-x pressures

Anyone auto-x on 205/50R16 or 205/55R16s? If so, what pressures did you run? I figured I'd start at about 45/40 F/R and see if I get any side-wall wear. I have 205/55 up front, and 205/50 in the back. I know, I should run the same, but I have quite a bit of tread left on the front, and I want to finish it off before buying 2 new ones, since I'm already pushing my budget with car stuff. They are both about the same as far as limit handling, so it's not too unpredictable, but of course I imagine I will see improvements when I run Fuzions all around.

I've ran on 215/50 and 225/50.

The 225/50 has roughly the same sidewall as the 205/55's (just a lot wider)

I ran 45 front & 42 rear. That was hot pressure. (you don't want the pressure to exceed the maximum when you are racing on them)

A good guesstimate "cold" is to drop 2 psi. Most Auto-X courses are only 45-60 seconds long. It's not like you are running open track.

If you want the tail to "dance" a little more (rear oversteer) then increase the rears closer to the fronts.

The problem with running much higher then low to mid 40's is the center of the contact patch raises considerably in comparison. Then you are actually having less contact patch press against the ground.

Put the newer tires on the front to make the car looser too.

If these are not dedicated racing tires (ie you daily drive them) use sidewalk chalk instead of shoe polish. Otherwise it won't wash off.

go to hardware store, and buy those white magnetic sheets you put on the vents for central air. they come in a pack of 3, for like 9 bucks or something. just cut out your #'s and your Class and you're good to go, just stick them on your doors. make couple diff # configurations in case your # is taken. remember you need these for both sides of vehicle.

it's a PITA to keep making #'s using tape, or isn't clean using polish on windows.

Or, you can print it out on paper nice and large, and just tape around the 4 corners to the door.

Shoe polish is a PITA to get off the windshield (mine was sitting the the windshield for weeks after the event.)

Electrical tape works as does masking tape (and if you forget the roll of tape the next week you can just pull it off and remake your new numbers .)

I bought a 4 foot X 24 inches roll of magnetic sheeting for $20 at the local Michaels that I have been cutting numbers out of.

Remember when cutting numbers that to be strictly legal the class letters must be at least 4 inches tall and at least 25% - 75% as tall as your numbers and need to have a .75 inches stroke width.

Class numbers must be at least 8 inches tall and need to have a stroke width of at least 1.25 inch.

Also stroke width must be at least 10% of the height.

for the winter series they will not care about your class being on your car that much (even more so since you are running novice) (actually DC SCCA might be the only local club that cares that much about what class you have listed)

If you know what number you are going to be on saturday (just pick something and put in in the registration) I can try to make sure I have that number in the big box of AutoX stuff that I take to the event so you can try out those type of magnets and see if you like them or not.