Calculating impeller speeds
Thread Starter
Joined: Jun 2002
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From: Colorado
Calculating impeller speeds How would one calculate the impeller speed based in the crank and blower pullies? Do anyone know the diameter of the 'normal' Procharger crank pullie? TIA.
Teching In
Joined: Aug 2003
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From: Rochester Hills, MI
Originally Posted by ls1290
How would one calculate the impeller speed based in the crank and blower pullies? Do anyone know the diameter of the 'normal' Procharger crank pullie? TIA.
Pulley diameters can be determined by taking a piece of string and wrapping it around a pulley (make sure string is in the rib). Measuring the string will give you the circumference of a circle. From that you can calculate the diameter of the pulley.
I know for LT1 cars the blower crank pulley is 7.65 inches.
Thread Starter
Joined: Jun 2002
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From: Colorado
Originally Posted by ls1290
What would the affects of running the blower at 86% of its maximum impeller speed compared to 71%? How much would the IAT increase?
TECH Addict
Joined: Nov 2001
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From: Bellevue, Wa
plenty have changed pullies but I doubt many if any have measured IAT differences between the 2
I can tell you p1sc, non intercooled pullied for 90% of max impeller speed my cruise IAT's would hit 150 on a 90 degree day.
I can tell you p1sc, non intercooled pullied for 90% of max impeller speed my cruise IAT's would hit 150 on a 90 degree day.
TECH Senior Member
Joined: Nov 2001
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From: Chi-Town, IL
Right now, with my D-1SC with its 4:1 setup, I'm spinning the blower around 14,000rpms before its max at 6000rpms, thats where I make peak power, and I'm only seeing 11psi 
I'm running a 7.25" crank pulley and a 3.4" blower
I ordered a 3.2" about a week ago
I'm running a 7.25" crank pulley and a 3.4" blowerI ordered a 3.2" about a week ago
