Thread: Electric fuel pump questions?

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This is all the fuel pump that any street/strip SBC motor will ever need.....
http://www.summitracing.com/parts/cr...make/chevrolet

Most of you fellows on this board have grown up with EFI, where more pressure makes more horsepower. That is not true with a carburetor. More than about 5 psi will overpower the needle and seat in the bowl and allow the pump to blow raw fuel into the intake manifold, creating a tuning nightmare for you. You do need large lines to provide good volume, but the pressure has to be limited to around 5 psi. Actually, many fellows have found that the Edelbrock Performer series of carburetor works best with a fuel pressure of 4 3/4 lbs. The Edelbrock design was taken from the Carter AFB, so the 4 3/4 lbs works well for those carburetors also. Holleys can generally stand a little more pressure before the needle unloads, but personally, I wouldn't run more than 6 psi on a Holley.......................... MORE PRESSURE WILL NOT MAKE MORE HORSEPOWER. It will only generate a nightmare for you because any tuning you try to do will be offset by the loading up of the intake manifold with raw fuel.

A lesson on how much fuel pump volume (GPH) you actually need......
Most any internal combustion engine will consume fuel at the rate of .5 (1/2) POUNDS of fuel per each horsepower hour at MAXIMUM power.
So, a motor under full power and making 500 hp will consume fuel at the rate of (.5 x 500 = 250 lbs of fuel per hour). Since fuel weighs roughly 6 lbs per gallon, we can divide the pounds of fuel used by 6 to determine the gallons used per hour (250 / 6 = 41.66 gallons per hour at max power). So, theoretically, a fuel pump that flows 42 GPH would supply enough volume of fuel to support 500 hp on a continuous basis. Most street motors will spend 99.9% of their life running between idle and 3000 rpm's, so don't let anyone talk you into more pump than you need. Most of you fellows don't have 500 hp motors and even if you do, how often do you ask the motor to generate 500 hp?

Sometimes us hot rodders are inundated with all the razz-matazz of the latest double-throwdown, cadmium-plated, triple-adjustable whiz-bang whatchamaycallit and buy parts that far exceed the actual requirements of good, sound engineering.

Math will never lie to you. There are no gray areas. I'ts all either black or white. It's either right or it's wrong.

Now, as far as installing electric fuel pumps.....
NEVER bolt an electric fuel pump directly to any metal part of the automobile. Always isolate the pump from the vehicle with rubber isolators or suffer the penalty of droning sheet metal which will make you crazy in short order.
http://www.summitracing.com/parts/wl...FcZZ7AodiXoAUg
Also, use short pieces of non-metallic fuel-rated hose to connect the fuel lines to the pump. Connecting metallic lines directly to the pump will make the aforementioned droning sound that you will not like.

I like to install a fuel filter before and after the pump. Of course, you have to keep an eye on the filters and keep the elements changed on a regular basis to prevent burning up the pump. This type of inline filter wil work well and allows changing the filter element with little mess.....
http://www.ebay.com/itm/High-Perform...-/190924601803


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