Thread: Fuel Pump for Blower 350

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I have seen somewhere that the rule of thumb is to figure out what the motor uses at full tilt and double it because of having to pull fuel from the rear to the front, against g's, through small lines, etc.

The motor will use around 1/2 lb of fuel per horsepower hour, so if you're making 500 hp, that would be 250 lbs of fuel per hour. If you figure that gasoline weighs about 6 lbs per gallon, that would be 41.66 gallons per hour at full tilt boogie. Doubling that would be 83.32 gallons per hour.

I wouldn't worry about the mechanical fuel pump being able to keep up with just a short burst at 500 hp, but if you wood the throttle for any length of time, I would want a fuel pressure gauge reading right at the carb inlets and not reading under 4 psi at any time. You know what happens if the motor goes lean. You want volume, not pressure though, so I would also limit fuel pressure to 5 psi max to prevent tuning nightmares resulting from raw fuel into the intake, blowing past the needle and seat. Use some thumb-size lines and a good regulator.

Thanks for the help, guys. I am going to get rid of my mechanical pump and move over to electric pump. Holleys RED standard electric pump. This way I won't have to worry about any clearance issues to the frame.

If you want a good pump look into the Gerotor style. The Holley Red, Blue, and Black pumps are rotary vane type and do not pull very good and are not as rugged as Gerotor pumps. You will notice a big difference in price; you get what you pay for. Holley, Mallory, Barry Grant and others sell the Gerotor pumps.

Kitz

The Holley will be ok but be sure to mount it in rubber mounts. Even then it is really noisy. I'd go with a gerotor type pump instead. they are more money but much quieter.

Minimum of AN-8 or 1/2 in lines from the tank to the carb distribution block.