I looked around the forum and searched but I couldnt find an answer. I was on the LFP website looking at the pulleys. It listed the hp increase of the 4lb. pulley as being 15 hp . and the 6 lb. pulley being 18 hp . I guess I might have been optimistic but I thought the 4 lb. would have been atleast 25 hp. then even more for the 6 lber Thanks for the help.

 

Peak HP measurements are less than useful for evaluating a pulley swap. The numbers you are citing are peak numbers.

A pulley gives greater gains in the lower RPMs than in the upper RPMs. If you compare full dyno charts, you will see this.

By the upper RPMs, the blower is overheating the air, so you don't gain as much there.

 

Makes sense. Alot broader power curve. I feel your pain dawg. I think the USSR moved to CA

 

I went from 15 to 18 PSI on the gauge with a 4# pulley, on my 2.3 K/B and made 40 RWHP more on the dyno!

Phil

 

Hey Tim, could your statement apply to long tube headers as well? I personally think so. (Out side the air warming up of course). But long tubes create alot more hp and tq low and midrange than just 17+ hp at peak? Yes No Figurativly speaking on a stock motor with 4lb and tune.

 

speaking since A dyno normally puts down 330-335 on a dyno...

my 4lb pulley took me to 401RWHP, and my 6lber took me to 420RWHP...

you do the math, but this is all based on a dyno tune... not a box tune that comes with the pulley....

 

Well, there are no shops within a couple hundred miles that I know about. My original tune came from Powersuge, so I'll probably get an updated one from Sal. Should be decent Thanks for the help.