since no one would answer my question i figured i start a new post whats the difference in the percentage of underdrive (i.e. 10% vs 25%). ive seen a crank and alternator pulley set and a "special machining required for use w/ SLP chain" is this only for that chain or is it more of a necessity??

 

The crank pullies are 25% underdrive. The alternator pullies are 10% or 25%. I would just keep my stock alt. pulley. The undredrive alt. pullies can cause low voltage situations. The machined ones are for double roller timing chain kits.If you have a stock or single timming chain you dont need one. ASP is the most proven out of the bunch. Tony

 

machining is for if you have a c5....and a double chain by slp..
no machining necessary on ls1 in camaro and birds

 

in other words a crank pulley is what i should get...just want to make sure i dont make newbie mistakes

 

yes, crank pulley is all you need. im running the ASP and dual rollmaster chain w/o problem, no shimming.

 

so what kind of rwhp should i expect? i know its not too much

 

from the pulley not much, its gains show up on the track more so then the dyno.