March pulley question for my GT.
 

I am reading on the website about their pulleys and I have a few questions.

link: http://www.marchperf.com/pg32.html

1. When the talk about S.F.I. FLUID DAMPENER and the 'non labelled SFI ones' ... what the hell is the difference? Why are they so much more?
2. What do you think of their claim of 12WHP? I have seen Steeda's claim at 8WHP for theirs... which even to me seems a bit high.

Any help appreciated here.

Oh ... how hard are these pulleys to install?

The SFI stamp would be the big difference since you need one once you hit 10s. As for the difference in the pulley who knows but whatever it is it apparently costs more. If you don't need an SFI approved pulley then I wouldn't worry about it. I would not bother with any kind of piggyback type pulley though.

Just like any other company that claims results take it with a grain of salt.

If I could have found these at the last race I would have bought theirs instead of Steeda. My Steeda crank pulley is now 3 years old and litterally separated on my car this past weekend. I had to buy another one between rounds and change it out in order to keep racing. The new one is SFI rated and works fine but I'm not happy that my original one feel apart.

Bill

I have wondered the same questions. What does SFI mean? I know we should avoid pigg-back. What exactly does that mean?

http://www.sfifoundation.com/

The piggyback style pulleys require that you remove and re-use your factory rubber damper rather than having the new crank pulley and damper come as one piece.

SFI is a saftey rating used in most racing bodys