What kind of gains are typically seen by adding a pulley? Track times? Dyno pulls?

 

Maybe 1 tenth,I had one before my supercharger install,if you install the lower you need the alternator pulley to,so the battery will stay charged.It's bad when you have rev the motor to keep your headlights from going dim at a red light.

 

Smoke_ur_5.0 did before and after dyno and just the crank put 12rwhp on a 5.3.

 

I find 12rwhp hard to believe,you might see that much if you removed the belt completely,3-5hp tops in the rev range our trucks operate,maybe 12hp above 6000rpm.

 

You might want to check this out. I belive it. It was one of the best mods I did not my truck.
https://ls1tech.com/forums/showthrea...ight=asp+crank

 

i think you should gain anywhere from 1 to 3 tenths. depends on the mods you have i guess. i had a nice jump in et after installing mine.

 

Did you have the e-fans before or after installing the pulley. I'm guessing you would see the biggest jump with the fans on.

 

i had the fans on before i did the pulley. to this date, my biggest gain has been the pulley. i just got 3.73 gears installed so i haven't had a chance to test them vs 3.42's. over all i was very please with the pulley. i did lose a little voltage at idle but not major in my book