i have a 2wd 79 Ford F250 with a 460. I am experiencing vapor lock on my truck. It happens on a hot day and after cruising about ten miles. What do I need beyond an electric fuel pump? And what particular specs should I look for in a pump?

 

If you decide to go electric...(1) get a summit catalogue and get either the carter (about 65) as it pumps at a steady 7 psi which is the MAX pressure you want going into your engine , (or) look at one of the 2 different Holley Pumps. They are more $$$, but putout more psi and more volume. (2)Mount the pump on the leftside frame rail as low as possible. Electric pumps have very little suction but strong output, so they need an unimpeded supply of fuel from the tank.(3) Install a clear fuel filter on BOTH the suction and the Pressure side of the pump. (4) I installed a 0 to 30 psi fuel pressure gauge that I got from summit along with a fuel pressure regulator which i mounted on the metal inner panel on the left side under the hood. (5) Remember!!!!! if your in a Wreck, that Pump is going to KEEP pumping gas. So if your smart you will install an oil pressure cutoff switch in Series with your power wire going to the fuel pump which will KILL the Power to the Pump When the OIL pressure goes to Zero,i.e. when the motor Dies!!!!! Remember ..you never want more than 7 psi of pressure being applied to the Float on your Carb or it will cause problems. good luck , s. kuteman

 

have you thought about getting a Cool Can. if you dont know what it is. it's a plastic can that you hook up to you fuel line as close as you can to your carb. you pack the can with ice and it cools the fuel before going into the carb. a friend of mine did this on his girlfriends car it work pretty good.

 

Great advice here, especially about the oil pressure safety switch. I've had very good luck with the Mallory comp 110 electric pump for non-return line systems and the Comp 140 for return line systems. They are quiet and dependable. In all cases you will need a regulator - 5 to 6 psi is optimum setting for most carbs. Holley carbs sometimes have some troubles with settings over 6-7 psi (needle gets pushed off the seat = flooding).

I am not convinced that you need an electric pump. In most cases, the stock mechanical pump is fine, it's mostly a case of heat buildup in the line to the carb and/or the carb itself. You may consider re-routing the line so that it might be in more of the airflow that's drawn in by the fan, plus insulating it as well. There are metal plates/heatshields available for the carb, or you can use a thin (1/4"-1/2") phenolic or wood spacer under the carb if space allows. I would do this first before doing the electric pump.

If you use a pump, as mentioned, place it low in the airstream and close to the tank so that fuel will tend to siphon into it and it can push, not pull the fuel. I ALWAYS install a safety cut-off switch plus I use a relay and a manual bypass. The bypass allows me to prime the carb with fuel first, then I switch it over to the safety switch side of the circuit. The relay helps eliminate running the full amperage draw of the load (pump) through the switch itself. This is more complication than you need, but I also wire in indicator lamps for bypass and fuel pump on. That way I have a visual reminder of what's going on. If for some reason a fuse or relay fails, the pump light will go off - gives me time to pull over before the carb bowl runs out of fuel.

 

My 460 does this too. I am going to put a high volume mechanical pump on it, either a Holley or Edelbrock.
Jimmy

 

i have a freind that experienced the same problem over ac ouple of years of trying all kinds of remedies. he has 79 f350 4x4 with a 460 transplant nad he lives in arizona with this problem. someone finally suggusted to him to get rid of as much rubber hose around the engine compartment that goes to the carb. he replaced all but a few inches of hose and yes this got rid of the vapor lock that took him years to get right. and yes he had installed the electric pump and regulator to fix this and used insulation on the lines to no avail. till he used metal lines. seems like rubber likes to expand in the heat and cause vapor lock. good luck!