pully size i needed?

[RedGTZ]

Hi!
I want to know what pully size i need to use to get about 7psi on an engine
that have a 5.5 inch crank pully and that will need this 7psi at about
6800rpm. My engine is a 2.3 Quad4 W41. Or can you give me the formula
to calculate it right?

Thanks for any help! ;)

[Chuck]

Well your application is a little different than usual. You have a very small displacement than that blower was intended for so you will see more boost than you think.

If that blower makes 6 psi on twice the displacement, I would imagine that with the stock sized pullies you would get nearly 10#'s. I am not sure about that but that blower is definatly not going to have to work very hard to make boost on that small of an application. You may find that you have to slow it down a bit with a smaller crank pulley or larger blower pulley.

[RedGTZ]

thanks for the info!

Is any formula is aviable to calculate this?

[Chuck]

The only formulas would be in regards to the speed that the blower is turning, not the boost ouput.

You will have to experimant with pulley's to get the boost level you want.

[RedGTZ]

right now i dont have any pully with it but i want to built myself a set in interchangeable pullys so i can change them to get more or less boost out of it. I'm a cnc machinist so it would not be a problem doing this.

Witch size did you guys recommend me to start with?