With my current setup (in sig) both Justin from Blackbear and myself feel the truck is maxed out on power. I am running a 2.9" pulley and getting 7 psi of boost at WOT. I, like any performance nut, want more. Is a 2.7" pulley the next logical step? If so, what would I gain in boost? How about power and torque?

 

I would do an 8 rib setup with an OD balancer and smaller blower pulley.

You gain about a pound of boost for each tenth of a pulley size you drop roughly is rule of thumb.And roughly 10hp give or take per pound .

Going with an OD crank balancer you should gain 2 or so lbs of boost .

So I would start with that , the OD balancer .it will help with belt slip , but going to a 2.7 or 2.6 you will see belt slip on a 6rib drive setup.

I did run a 2.6 6rib and an OD balancer so it can be done but like I said I had belt slip.

Boost is wayyyy more fun at 10psi + , I def think you have power left on the table , just make sure you get a great tune and fuel system to support the extra boost.

 

Do you think I still would have belt slippage with my added idler below the snout pulley?

 

Only one way to find out bud ! Try it ! I'm sure it will run good with a retune and small pulley , but up top I bet you'll still get slip , maybe not as much as without your idler but prob still some , Leftcoast32 knows all about this subject.

I def first would do the larger OD balancer , that will get ya close to 10psi and will help with belt slip IMO.

But yeah it's def recommended to switch to 8 rib when you pulley down that small

Edit: I have a 2.6 6 rib pulley from south Florida pulley if ya want it 60$ plus the ride . I think I paid 120$ for it , the reason I'm posting is its just hanging on my wall lol

 

How is your cam with boost? Mine is very similar!

I'd follow Tim's lead on this one... he seems to be doing pretty well with his truck. I want to do an 8 rib as well...