converting lbs per hour...

Discussion in 'PSI Superchargers Tech Questions' started by Danny Humphreys, Apr 23, 2008.

  1. Danny Humphreys

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    Anyone know how to convert gallons per minute to lbs per hour? Is it as simple as taking the weight of a gallon of alcohol and doing the math to convert to minutes to hours? I need to know what 14.5 gallons per our translates into lbs per hour. Thanks!
     
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  2. Mike Canter

    Mike Canter Top Dragster
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    Methanol weights 6.63 lbs per gallon. Multiply 14.5 GPM by 6.63 lbs which means you are flowing 96.135 lbs per minute. Times 60 minutes is 5768.1 lbs per hour.
     
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  3. Brady

    Brady New Member

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    In a blown application, how many #/hr methanol is required per horsepower? Roughly, obviously. I'm thinking ~2? Is there a formula?
     
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  4. Mike Canter

    Mike Canter Top Dragster
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    No formula that I know of but from HP figures that I know about and required GPM it appears to be in the 1.50 to 1.75 pound per hour per horsepower in a Rootes supercharged motor. There are a lot of factors involved because if a Rootes blown motor makes for example 2500 HP out the flywheel it really requiring around 400 hp to drive the blower so the motor is really making 2900 HP and requires the fuel for that. So which HP figure do you use for computation, the out the flywheel HP or in the motor HP? A screw blower making for example 3200 HP requires around 150 HP to drive the blower so really makes 3350 HP internally. Now if you throw in a turbo motor it doesn't use up motor HP to drive the turbos so you can see around 3500 HP out the flywheel. So it is hard to compute one BSFC for all blown applications.

    Those are my thoughts on it. :D
     
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  5. WJ Birmingham

    WJ Birmingham New Member

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  6. Brady

    Brady New Member

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    Thanks for the info. I've got EFI, I'm flowing about 5320#/hr at 100% duty cycle. (which I only see for a split second at the gear change). It's with a centrifugal (Procharger) supercharger, I have no good idea what the parasitic losses are with a centrifugal supercharger, I'm betting it's close to 200hp...

    I was actually curious because I'm helping a friend size a fuel system for his turbo setup. Thanks.
     
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  7. Brady

    Brady New Member

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  8. TOL

    TOL Active Member

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    You DO NOT want to ever have more than 80% duty at an EFI injector. You might want to crank up the base fuel pressure. Drop me a PM and we can talk about your system.
     
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