i have heard from some drag racers that turning directional wheels backwards means more grip in the straight line. the con of this would be no traction turning, but for a straight line use only would this work? im curious for the next time i go to the track. anything for free that will get me into the 12's ill take. what is your input
kris

 

No, it shouldn't affect your grip. The only effect should be the tires' ability to displace water when running in rain since the grooves will channel the water forward instead of rearward, which is not effective when going at speed.

 

Wheels or tires?

Wheels, I would think it would have no noticable effect.

Tires, I wouldn't expect big differences, but the difference would probably depend a lot on the tire in question.

-Max

 

Directional usually refers to the tire's tread pattern, and that tread pattern's ability to displace water effectively. It should have nothing to do with straight line grip. I would think low rolling resistance would be more helpful than turning reversing directional tires. AFIK, Pirelli P6000s were designed with low rolling resistance as an important parameter. I think most tires are designed to have low rolling resistance, but it's tough to compare this parameter between tire manufacturers. FWIW, I've run directional RE71s backwards to get more mileage out of them. At that point the tread was down to 4/32 so the RE71's water channeling abilities was already approaching nill anyway LOL

 

FWIW, rolling resistance is proportional to the tire's section width. The wider the tire, the higher the rolling resistance. The narrower the tire, the lower the rolling resistance. Obviously the narrower the tire, the less contact patch available for cornering. This is why you see Bonneville salt flats land speed record racers running very skinny tires, and you see F1 racers running very wide tires (considering F1 racers weigh only about 1500 lbs).

IMHO, 255/40-17 tire size mounted on 9 or 9.5 x 17 wheels all around strikes a beautiful balance between low rolling resistance (maximum top speed), straight-line acceleration, straight-line braking, and cornering grip.