I wanted to start a thread where people posted their pulley size and engine size with the resulting psi. Adding which blower kit you are using will be helpful too. If you are using an intercooler or aftercooler, that info would be helpful for informational purposes. I've got a 3.8, 3.4, and 3.2 for my novi 1220. Looking to get ideas for which to use, but this information will be helpful to a lot of people. One thing to remember is that PSI is not everything. CFM has to be taken into account as well. As a general rule, the 1220 will make less power than the 1200 at the same PSI due to the CFM rating.

Novi 1220

CoolGuy094: AP1 engine, Novi 1220, 700ft above sea level
4.8" = 6-7 PSI
3.4" = 14-16 PSI
3.2" = 16-18 PSI

rmerchant3: AP2 engine, Novi 1220SL, 89ft above sea level
3.4" = 12.2 PSI

Novi 1200

pwrinxs: AP2 engine, Novi 1200
4.0" = 8.3 PSI

s2000Junky: Custom engine, Novi 1200
3.2" = 16.5 PSI

LDfavoriteson AP2 engine, Novi 1200
3.6" = 16 PSI

 

It's not that simple. Results vary so do it and see.

 

If you're going standalone ECU then I personally would just put the 3.2" on and be done with it. No reason to jip yourself out of more boost.

 

From my personal experience:

AP1 motor
Novi 1220
Comptech aftercooler
~700 ft above sea level

4.8" = 6-7 PSI
3.4" = 14-16 PSI
3.2" = 16-18 PSI

Lower number was when it was hotter/more humid. Higher number was when it was colder/less humid.

 

I think we could get a general average though. I would love to try them all and see, but for the sake of my wallet and my tuner's time he'd like to have the one on that we need to get the goal I'm looking for. I am shooting for 375-400whp. He seems to think the 3.4 will do the trick, but across this board many seem to go with the 3.2 to reach those numbers. I have seen evan's tuning reach 400 with the 3.4 as well. My biggest thing is to keep it safe and rich. I don't want to have to lean it out to reach the numbers on a bigger pulley.



That's some good info. 14-16psi seems plenty. I would assume on an ap2 it would be 13-14.

I'll post my experince on here too when I get mine done.

 

If your trying to hit 400 WHP with a Novi 1220 on an AP2, then you should go with the smallest pulley available. Like you said, the 3.2" on your car with the lower red line might only make in that 14 PSI range versus the 16-18 that it made on mine. And even at 16-18 PSI I was at like 390 WHP but E85 put me over that tipping point. The Novi 1200 flows more CFM and allows for more power at similar boost levels compared to the Novi 1220. We are at a bit of a disadvantage.

 

I have a 05 ap2 I'm on 3.6 or 3.4 (can't remember at the moment) and a novi 1200 the car made 16 psi

 

I'll throw the 3.2 on just to be safe. You can always throw more fuel at it to bring it down.

 

 

Its interesting that you guys all go for the smaller blower pulley which the smaller you go the more belt slip you will deal with. Why don't more of you use the crank pulley as an option to not only keep better belt wrap but also to increase boost. ASP is making me a 6.5 crank pulley (vortech uses a 6" crank pulley). This will allow me to see a few more psi without introducing belt slip with my current 3.8 blower pulley setup.

I suspect its more related to cost then anything else.