Pulley Sizings, warranty & where to buy?

[99CobraP1SC]

I have a 10PSi pulley. I was informed by another web site that it is 3.4" pulley. What are the smaller sizes available in PSI and Inches ( For example, I also heard that a 3.0" is 12 PSI)?

What max size pulley is supported by ATI's warranty for a P-1SC. I heard it was no higher than 10 PSI pulley (I would not say that source was very knowledgeable and he was told by a friend). If higher than 10PSI, then where can you get smaller pulleys other than from ATI?


John

[WA2FAST]

My buddy has both the 10lb and the 12lb pullies. He got it directly from ATI... I suggest calling them up, I know for a fact that 12lb pulley does not affect the warranty so don't worry about that. I think the pulley was like 125 or so, but what can you do. Their number is (913) 338-2886. I would call them up and if nothing else see what the diameter of the pulleys are for different boost levels.

Just remember, boost is relative to RPM and your setup... so if you were to shift higher, you would make more boost... if you got better heads and intake and exhaust, you would not make as much boost as you did before all of that. If you have a fairly stock engine and are shifting within factory limits, then the size should somewhat accurately tell you what kind of boost to expect.

[99CobraP1SC]

I am 90% complete with my power pipe MOD. THis should give me more boost, so I need to see what I get. I am anticipating 11-12PSI max, from my 10PSI pulley. So if that happens and I were to get a 12PSI pulley I could see 13-14.

My engine internals are stock. No plans right now to change. I might be stuck with a 10PSI pulley unless upgrade my internals.

My current my goal with stock internals is 490-500 RWHP MAX. I might be close to 480-490 with the power pipe.

John

[WA2FAST]

Just be careful... 13-14 seems to be the magic number for floating the heads. Not fun when you do that. It doesn't actually cause any damage, just blows your head-gaskets rendering you pretty much stranded where ever you are along with forcing you to buy head studs which are fun to install on a mod motor... especially DOHC. It isn't like my car that you just slide the heads over once they are in... there is no room in your engine bay for that since the heads are so damn big. Anyway... see what the power pipe will do for you, I am interested to hear, and then go from there.