Thread: Fuel System Setup

Tweet

Quick question; I have a 1978 chevy P/U with a 454 BBC and was wondering if I have my fuel system set up correctly. I have a (three line fuel sending unit) in my fuel tank. One line is a supply line, the second is a vent line, the third line is a fuel return line. I have the fuel supply line from the tank going to the fuel pump, the vent line vents at the gas tank sending unit, and the fuel return line goes from my regulator back to the tank. My regulator is located after the fuel pump and before the carburetor. The fuel regulator has two outlets, one going to the carb and the other is going back to the gas tank as a fuel return line. Do I have this system setup correctly? When the truck is at idle the fuel pressure gage flutters. The gage is located just before the carburetor. Thank You......DET45

The problem with stock sending units and tanks has always been delivery. Venting is critical, and some fuel pumps do require a return line. Now the lower end cheaper electric fuel pumps will cause the gauge to flutter, this has been my experience. I got rid of the stock gas tank out of my camaro, and went to a fuel cell. I also bought an SX inline fuel pump and new return line regulator.My fuel pressure is rock solid, the gauge doesn't bounce. The real bonus was that i only lose 1/4 Lb fuel pressure on the top end even under the load of nitrous. So yes there is a definate gain to be had in proper fuel delivery. You may want to add a drop sump onto the bottom of your tank, if you want the stock tank? and calculate the fuel NEED /DEMAND of your current motor. then buy the correct pump etc for your application. I know many a racer who said he had no idea why his car stumbled ? till he realized he was running the bowls out of fuel by the top of first gear. The pump just couldnt keep up with the demand of the motor. Plus you have to consider when the car launches, it is creating a certain amount of force the the pump also has to try to push against. Go to the barry grant site and look at the fuel delivery section, very good info there.

http://www.barrygrant.com//bgfuel/de...1#FUELDELIVERY

Originally Posted by DET45

Quick question; I have a 1978 chevy P/U with a 454 BBC and was wondering if I have my fuel system set up correctly. I have a (three line fuel sending unit) in my fuel tank. One line is a supply line, the second is a vent line, the third line is a fuel return line. I have the fuel supply line from the tank going to the fuel pump, the vent line vents at the gas tank sending unit, and the fuel return line goes from my regulator back to the tank. My regulator is located after the fuel pump and before the carburetor. The fuel regulator has two outlets, one going to the carb and the other is going back to the gas tank as a fuel return line. Do I have this system setup correctly? When the truck is at idle the fuel pressure gage flutters. The gage is located just before the carburetor. Thank You......DET45

what do you have? a st. car or a full out racer. what you have is ok for the st. up to 6,000 rpm. you need to know what pressure you have at the carb. at the hights rpm's that you turn.

Plus you have to consider when the car launches, it is creating a certain

This is very true, you wouldnt believe the amout of force the fuel and the pump have to overcome when the car is accelerating. The fuel line size has a huge effect on this also.