im about to bite the bullet and go with the 3.0 but if i can get the 2.75 and make more boost ill get that one instead.ive read that it would only push out hot air after a certain point,but i dont understand what that means really.

 

Once you exceed the efficiency range of a turbo or supercharger by over-spinning it, the HP gains made from additional boost are less per psi of additional boost and air intake temperatures increase, as well.

That being said, I have no idea if a 2.75" pulley would over-spin the Novi1000 on an AP1 F20C.

Can anyone chime in?

 

i guess im having a hard time figuring it out since sos changed their pulley boost amounts.i have the 3.2 and saw 9.5 on the dyno with the fmic.sos now says 3.2 makes 11psi @9k if the blower is good for 15psi then the 2.75 should make 13.5 or so.

 

The thing is, we should be looking at RPM's and not boost pressure. I am running a header-back exhaust system and, due to the lower restriction, I see less boost pressure than someone else might on a stock exhaust. That doesn't mean the blower is doing any less work.

I'll have a chat with Paxton at some point.

 

good point.i know the numbers are around somewhere about how to figure out max impeller speed.55,000 is the max i believe so now i need to figure what a 2.75 would spin the blower to.

 

I'm running 3" for 13.8 lbs.. It is my understanding that 14lbs. is max risk without building the bottom end. Also I've heard that the comptech is pretty much maxed out out this rpm.

 

thanks i will be ordering the 3.0 tomorrow