Originally Posted by hotrodharley
will i get more blower wine from the 8mm or the 13.9mm pulleys/belts?was told the blower wine comes from the air between the pulley and belt. right or wrong?
Correct. It's the air escaping out of the teeth as they mesh together.
14mm pulleys are cheaper as they are less used now. Most people have moved over to 8mm for a greater selection of ratios, and the newest Pro-Mod and Top Fuel stuff is 11mm, which is the best blend of ratios and strength.
As for amount of whine... meh... I've had both, and they are both pretty close in volume.
How tight you run the belt has a bigger impact on whine than anything. The guys with the most whine (for street driven) usually have belts you can play like a guitar string. Doing that is really dangerous because it pre-loads the crank snout pretty heavily. The snout will give before that belt will.
If you want to reduce the amount of whine, you can drill 1/16" holes into the tooth valley on the pulley. It gives the air more places to escape and minimizes the whine sound.