No difference in 2.95 & 2.75....

So i finally pulled my 2.95 pulley off (made a max of 12.5psi... 11psi where i usually shift) and put my new 2.75 pulley on. I went out and made some test runs and it still only made just over 11psi @ 5800 :confused:

I know it wasnt slipping, as it held boost strong and never dropped off... so i dunno what to think. It seemed as if the boost came in a little quicker. Im gonna pull a plug and see if its running too rich or not (peak fuel pressure was 53psi). Only other thing i can tell might have lost a pound or two was the IAT sensor started coming out, and the line for digital boost guage popped off.

You may be getting to a point where you are over spinning the s-trim and are creating more heat. What size is the lower pulley. 6.87"

Do you have good heads or intake.

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Originally Posted by BLOWNBY

You may be getting to a point where you are over spinning the s-trim and are creating more heat. What size is the lower pulley. 6.87"

Do you have good heads or intake.

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Yes im running a 6.87 lower. I have lightly ported Performer 6037 heads, and Extrude honed Performer RPM intake, 70mm TB.

With the 2.75/6.87 setup @ 5800 im turning it 49,988.62.. where it made just a little over 11psi.
With the 2.95/6.87 setup @ 5800 i was turning it 46,599.56.. where it made a max of 12.5psi.

Im takin it out tonight so ill see if it makes anymore since it blew off the line for my digital boost guage, started blowing out the IAT sensor a little. So ill report back on what it does.

put an anderson power pipe on it I'm betting you are still running the stock 3.5 inch inlet yes this restricting flow to the blower guy ,and over spinning your blower won't hurt it in the quater mile ,I'm running a 7.5 crank with a 2.75 blower pulley ,17psi and no problems for years.