Just got the following message from Drew:
So it does seem that there is a difference between AP1 pullies and AP2 pullies due to the crank size differences(I'm assuming).

Can anyone with an AP2 measure their pulley size and post their max boost level?

 

Here's D-S2K 3.7" pulley size and boost info:

anyone else?

 

I had 3.15" inch Pulley if I remember correctly, and it boosted to 13 psi by 8,100. I would not reccomend doing this on a stock motor as we all know what will happen

Call drew at tech2motorsports and get him to custom make you a 3.30" pulley. Set your redline at 8,500 and get 750cc's with EMS. Have some who reallllllly knows what he's doing tune your car and it will be butter.


I have my pulley that I used still sitting at my house. I will sell it and the belt you need for it for $100.

You should get a headgasket and then get my pulley and your car will be fast as shit. I had mine running great for 2 days before the pistons melted and the rods broke and I raced a few people on the street. One car was in the high 12's and I walked him and the other was a 12.3 car and he beat me by a bumper. So just to give you an idea, with tires and a PERFECT run that setup can hit high 11's. By the way this was with stock exhaust and cat and no header.

 

What? Are you insane?

There is no difference between an AP1 pulley and an AP2 pulley. It just that with any particular pulley you will get less boost on AP2 because of the lower redline.

Didn't you read the thread before posting. Hell, even the email you quote confirms it.

 

I think you may have been mistaken... As per Drew's comment:

The only thing that is confusing is that Drew states his 9psi pulley measures 3.5" and D-S2K's measures 3.7", but his car pushes 9psi at 8K

I know it has to do with the redline on the AP2s, but I believe it also has to do with something else, just trying to figure out what that other thing is

 

OMG

If you get 9psi at 9000rpm you get 7psi at 8000. What's the mystery?

 

What's up with the sarcasm buddy??? I'm just trying to figure out which size pulley I should get and wanted to get members input on their setups. Why do you feel the need to riducule my questions?

Thanks for all your help

anyhow, so far I have collected the following info. on pulley sizes and boost levels:

AP1 3.25" pulley made 12.8psi @ 9350 rpm
AP1 4" pulley made 7psi @ 9000 rpm

AP2 3.15" pulley made 13psi @ 8100 rpm
AP2 3.7" pulley made 9psi @ 8K & 11.5psi @ 10500
AP2 4.2" (stock AP2 comptech pulley) 5.5psi @ 8000

 

I'm sorry, I just can't for the life of me work out why you don't get it. It's real simple. Even the email from Comptech confirms it.

Ok, so it's not so simple. Boost is dependant on more than just pulley size. It's also dependant on whether or not the owner has charge cooling and the condition of their belt for example, and even how accurate their gauge is.

But here's the facts:
An AP1 and AP2 owner have the same Comptech SC, AC, and the same size aftermarket pulley. They are both using the same gauge and are in the same location at the same time. Both of their belts are tightened correctly and they are getting no slippage. At 8200 WOT they will see the same boost (within error margins).

But of course the AP1 isn't yet at redline so it's max boost will be higher.

 

No need to get so worked up ...

 

Hey, just answering his questions, whether he wants the answers or not.