dfw

**46Tbird** · 08-19-2013, 11:01 AM

Originally Posted by SlowGreyGT

That won't help at all unless they are drag radials. The sidewalls on a regular street radial do not flex therefor do not benefit from lowering air pressure at all.

Most modern tires recommend 35-45psi for fuel economy and there is NO WAY you're going to be able to hook up on a rock hard 40-series tire with ~400hp and a stick. There is a difference between "take some air out" and "take it down to the air pressure you run in a slick." Most of these guys would get a better launch at ~25psi than they will at 40.

*edit, treed by junkie

**Ear rak** · 08-19-2013, 12:02 PM

Originally Posted by 46Tbird

Most modern tires recommend 35-45psi for fuel economy and there is NO WAY you're going to be able to hook up on a rock hard 40-series tire with ~400hp and a stick. There is a difference between "take some air out" and "take it down to the air pressure you run in a slick." Most of these guys would get a better launch at ~25psi than they will at 40.

*edit, treed by junkie

This.

Taking air out of a street tire is not to make the compound work better, but to let the tire have more give.

All I know is, every time i've gone to the track on street tires, i get better 60 foots with the tires around 24-25 psi compared to 35psi