Tom Suddard wrote: That's really only for track work. For the street you chalk across the face of the tread and look for even wear.
Never thought of it that way. My luck all the chalk would go away...
Tom Suddard wrote: That's really only for track work. For the street you chalk across the face of the tread and look for even wear.
Never thought of it that way. My luck all the chalk would go away...
It will eventually, but on the street just drive a mile or so and see where the chalk is worn most. You don't have to wait for it to be completely gone.
Datsun1500 wrote: Doesn't every tire have the maximum pressure written on the sidewall? I usually put them a few pounds less than that.
Reminds me of when I bought some Pirellis at a Sears store. I started driving home and they rode like wooden wagon wheels. Drove back to the store and turned out the installer had pumped them up to 42 lbs, which was the max pressure on the sidewall. He said he had been installing tires for 20 years and had ALWAYS pumped them up to max pressure because that was the "correct" pressure. I guess I figured out why he had been a tire installer for 20 years and not a rocket surgeon.
I don't think the max pressure on the sidewall has anything to do with the proper running pressure except by coincidence.
I usually start with whatever the doot jam says for a fully loaded car and go from there.
Most any street tire is designed for the 32-35 psi range. Any change from that is a matter of personal preference.
The chalk/shoe polish is good for autocross to check tire rollover. Other than that, it is not much help.
The door jam sticker (on older vehicles) usually give the pressures based on tire size and vehicle load. The new EPA decals only give one pressure rating, which is for the set of rims/tires that actually came on the car.
Just the other day I had two 06 BMW 330i in my stalls. One sticker said 29/33 and the other listed 33/38. They had different size wheels, otherwise same car, same weight.
Once you change sizes that aren't listed, seems personal preference at that point. Although we do have a reference book laying around that is supposed to list tire pressures for aftermarket wheels and tires.
Stock ZX2 said 32, the SR said 35 with performance tires. Many owners manuals will suggest raising the pressure by as much a 4 psi when carrying heavy loads.
You'll need to log in to post.
