Miles in Michigan

I'm curious if the 5lb pulley will avoid some of the problems that occur with the 7lb or larger pulley. Belt slippage, stock fuel pump capacity, detonation, difficulty tuning, and whatever else can happen.

How much power will an ATI with a 5lb pulley make on a stock C5? I think I could expect about 450rwhp with the 7lb pulley on my stock LS1 6 speed. Never seen a dyno with the 5lb pulley, though.

Also, how much horsepower are LT headers worth on a supercharged car?

Thanks,
Miles

Mad_Dog

I can't answer your question but I believe ATI claims about 50 HP less than with 7 lbs. Problems should be considerably less with the 5lb system. You can always go with 7lbs. or greater later.

I changed my order earlier this week to a 5 lb set up due to reliablility questions being given in a number of posts on this forum. Fuel delivery and belt problems should not exist with the 5 lb system. I just hope ATI does not retard the timing as much as they apparently have on the 7 lb system. I am getting AutoTap to do before and after data logging to see just how good the programming is which seems to be a real weak link in the ATI package.

Mad_Dog

The following clip is from "HIGHRPM" on another thread. Seems to add validity to using the 5 lb system.

"Generally when a piston burns the fuel/air mixture is too lean.....this is not the fault of the supercharger....the fuel/air mixture is off. Without a dyno tune you were making educated guesses about your fuel requirements. Superchargers work great when the supporting hardware is configured properly....running high boost on stock motors without upgrades to other systems is a bomb waiting to go off. I'm building a 427C5R with ATI S/C...9.0 compression, all forged gear and only 5-6 lbs of boost.....this motor will produce well over 600RWHP and have good reliability.....trying to squeeze large amounts of power from small (4.6 l) stock motor is not going to give you reliability. Big power costs big $$$ there is no shortcut."