Hi,
Our kit is engineered using Aircraft Grade Billet 6061 Hard Coat Anodized Aluminum. After months of R&D in house and overseas (various climates & conditions) we concluded that there may be a slight power increase by going smaller than our pulley but the trade off is a chance of making the engine run hotter or possibly overheat (we noticed this in both DCT cars and Manual cars on and off the track), we choose reliability over that extra 1-2 rwhp that we may get from a smaller pulley. Testing in Miami, FL and in other hot climates was a must in our R&D process to take things to the “extreme limits”.
Another key element in the development of the Signature Pulley Kit was to retain the “Factory Crank hex Drive Adapter”, this was important to keep this factory feature for its inherent purpose. The pulley kit does not modify factory harmonics or dampening. Stronger side walls were the last key element in choosing our size over a smaller design.
The Active Autowerke E9X Signature Pulley Kit yields gains of 12+HP on a completely stock car.
A replacement double sided belt is also provided just in case
Please see our current $50 off offer here
http://www.m3post.com/forums/showthread.php?t=757275