Underdrive pulleys for street racing

[typeR]

the gains in an undrive pulley set has very little to do with undriving the accessories and almost all to do with the dramatic weight difference... my crank pulley was 8lbs heavier than the light weight aluminum one i bought and am choosing not to install eventhough it has been dyno proven to provide 10/10 in my car and probablly much much more below where a dyno jet can measure....the concerne is the resonance effet on the crank it self ...skyscrappers use HB/TVD's to diminish harmonics that could literally rip a building to shreds in its absense...if steve saleen came on told me why the absence of the hb/tvd isnt a problem and only really effect cabin noise id be all over it but as it stands the best testiment agaisnt it comes to me from a company called AEM they have this civic draggster running low 8's and it has the o.e. crank pulley...also they make pulleys but not crank pulleys just accessory pulleys