I have a 2001 with a JL chip and a K&N filter and boost actuartor adjusted. It pegs the boost guage now. Stock it only ran 8lbs and now it looks like 11lbs. It runs very well. Wahet are the real word improvements with a 4lb pulley? How much faster and where?

 

Im not a Tuner by any means but I dont think any of the mods you currently have should have givin you more boost.I have some of the mods you have and I didnt see a change in boost until I installed a pulley.By the way I have a 3# pulley and my autometer gauge says about 11#s of boost.Hope this helps..

 

I am not sure why, but many of the people who adjusted the boost actuator report seat of the pants difference and boost improvements. My truck would stay in the vacuum state stock untill about 1/4 - 1/3 throttle at 60mph cruise. Now it starts almost as soon as I apply throttle. Maybet it starts building boost earlier and therfore can maintain a higher boost. In 3rd from 4500 on my gauge is pegged. Stock it never went over 8lbs.

 

A chip and pulley will alow the blower to spin up higher and breath better allowing alittle more boost. With you 4Lbs pulley, you can expect about a four tenths drop in the quarter. But traction will be a bigger issue than what it is now.

If you just drive your truck around on the street and have fun now and then. I would only go with a two. But if you go to the track now and then, or offten for that matter, I would go for the four.

 

Is that a K&N filter panel or cone filter. The boost actuator adjustment can easily give you a 1/2# of extra boost depending on where it was to start with.