I am looking to get a little more power out of my setup. Must still be daily driveable and tow safely. I guess if it would be pushing things for towing then I could go back to stock for summer when towing in heat.

6.0L LQ4, I have a larger rad, and larger heat exchanger for intercooler, and intake, coolant, and KR readings in truck to keep an eye on things. Only mod to truck that should affect boost is a different muffler (may not do anything). It is currently at 4.5 PSI, and has 2 bar tuning that can safely accept more boost.

Here are a few questions:

1. How much RWHP/RWTQ gain does 1 PSI get you, on average, and at 700m elevation?

2. How much pulley size change gets you 1 PSI gain, with no other changes?

3. If my current pulley is 3.2, what size would you recommend to put on to get about 40-50 more RWHP? Is this possible? Or should I just go to smallest pulley and pin crank?

4. What size belt would go with your recommended pulley?

Thanks to all who can help me.

 

I would pin the crank in any case and go with a 2.9 pulley, you should see your 40-50rwhp

 

0.3 would get me that far? Cool. Any idea on belt size?

 

I run a 112.5" with a 3.1 pulley, a 112" would take up the slack as we are talking very little size differences

 

forgot to mention, I'm running twin 100mm idlers so your belt size might vary a 1/2" or so

 

Thanks. I don't know much about pinning cranks. Is there a kit? Or do you just drill and tap a hole, and then install a small allen bolt?

 

Magnuson offers a kit that comes with a replacement crank bolt. JPA stocks them.

 

I am sure someone else will let me know what size belt to run that has stock pulleys. Why must we be adicted to power?

 

i thought you had a 3.4 or a bigger than radix stock pulley? hmmm.

yeh, .3 will get you a lot. But it will also make for hotter and quicker rise IAT temps. Bare that in mind. Belt size on a stock setup with 2.9, uhhhh say 111.5 down to a 111.0. At my elevation I went from a 3.0 pulley to a 2.8 pulley. My boost went from 7.5ish to 8.7ish. In the real cold weather I can squeak 9.2#'s. Not sure of HP quotes. It ranges with different systems. moregrip is probably real damn close with the hp quote.

 

lol! no kidding huh .............the other thing is tuning, you'll need some