Underdrive pulley

[Zrun]

Did anyone tried performance underdrive pulley?

 

I heard that it is the modification that will produce significant results, though not as much as turbo. Hehe. A website says that it improves hp all thru the rpm range.

 

Quote

Unorthodox Racing Underdrive Pulley - Now this is when I felt something. The car accelerates a little quicker, and flooring it will get you to speed (and higher) a bit quicker. My idle is actually smoother now; there are no vibrations, no problems with charging the battery, and my AC acts no different. It's long term reliability is still under question, but I don't forsee any problems. I've driven my car fairly hard since I had it installed (2.5+ years and counting) and if it wasn't balanced or would cause some immediate distress on my engine, I'm sure I would of noticed it by now.

 

Is any there drive belt alterations after the pulley is put on? I am asking this because if the shape, size and specifications of the pulley is exactly the same as factory, I can get any mechanic to put it on for me, if not, I'll have to find one who knows how to tune the car well to the new pulleys..

[Turbobrick]

Not many I know play with Underdrive pulley here. Not that popular but theoritically it should work pretty well as it reduces the load on the crank.