the pulley i have is measured at 3.5 and we were told it was a 7lb pulley for the comptech, but, one of our friends is pushing 16lbs on a vortech witht he same size pulley, this is why we are confused

 

i purchase a 4" pulley (comptech) from ASP Racing and i get about 7lb and sometimes get 7 1/2 lb of boost.....

 

Apples to oranges. The Vortech has a larger crank pulley AND is a different system.

 

4" is 7lbs and 3.5" is 9lbs. Anything lower than that is unknown because not that many people go there and there are many variables that come into play.

 

The pulley in question measures 3.400" OD. It MIGHT be considered a 3.5, not sure. So if it turns out to be a 9psi, which we will use on an aftercooled setup...

The new question is, what more will be needed over the VAFC to safely tune it.

IE:

Regulator (not sure of the Comptech's max capabilites)
Injectors
Add. management (E-manage)

 

Others will disagree, but I would ditch the V-AFC and FPR and go at least E-manage and larger injectors. But personally I wouldn't go smaller than a 4" pulley without AEM.

 

Anybody looking for a 9psi pulley?

 

I've got both the 7# and 9# for sale, Bill.


BTW, 3.25" was never calculated by me to be 12#. I believe it was closer to 11-11.5. It was always BN's notion that he wanted 12#. Personally, I think the 3.25" pulley will serve both of us very nicely.

 

i think bill will be very interested in that 7lb pulley, so the 7lb pulley you have measures 4 inches???

 

It'll be pulled off next week. The 3.5" and 3.25" ones are currently in front of me.