Where did you mount the electric pump?  No disrespect intended, but the joy of putting an electric pump on those older pickups with the tank in the cab is no matter where you put the pump, the tank was always higher and it easily gravity fed the pump.  Electric pumps push (pressure side) very well but don't pull well at all. (vacuum side)  It can be difficult to put a pump close enough to the tank and lower or as low as the bottom of the tank in many cars.  If you had to compromise on your pump location, maybe it isn't getting enough fuel to be effective when you really need it.  Another thought would be to carry a bottle of water with you and wait for it to happen again.  When it does, instead of waiting the ten or so minutes, pour the water over the fuel pump to cool it immediately and start the car.  If it starts and runs, at least you know you're dealing with vapor lock.  If it doesn't, you need to start looking for another problem.  Old trick but I know it works.

If the mechanical fuel pump on it now has been on it a while I'd put on a new one and see how it does. I had a new one go bad after several months on my 56 tbird and that cost me my runs in columbus Ohio a few years ago. Make sure the gas tank is vented as well, I hardly ever here of 56 fords vapor locking unless the gas line is too close to some sort of heat source. again I would check for vent not working from gas tank or a bad fuel pump and float level being correct in carb and viton needle seat not sticking in carb.

-Gary Burnette-

No Charlie, it never did it with the 2bbl but I never had the conditions where it vapor locks when it had the 2bbl on it. You know at a cruise how you just poke along for a long time. Ya know like "draggin' Main St." back in the day. I don't know if you know Cario Ga. or not but it's a little town, maybe a dozen blocks where they cruise. Turkey Rod run is a lot longer. I can drive the car all day down the road and through towns with a lot of traffic lights and it never misses a beat. If I park it and just let it sit there and idle for a long time it will do it too. That's about the whole story.

Doing Fords for 45 years. '56 Customline Victoria

E.J. in Havana FL

Speedpro & Speedbump, it's a '56 car not a pickup. The pump is mounted on the forward wall of the trunk. It comes out of the tank and goes up about 2" and into the pump. It has a new gas tank and all new vent plumbing. Good idea about cooling the pump though. You'd think if it was a weak pump though the place where it would run out of steam would be haulin' buggy and it never misses a beat there. Should be the same with a vent problem. Basically idling shouldn't be a problem as much as hi power as far as venting goes.

Doing Fords for 45 years. '56 Customline Victoria

E.J. in Havana FL

Is anything different that could be raising under hood temps above normal? Like Headers or A/C. How about something that would change air flow through the engine compartment like a belly pan of some type? Do you have a stock fan or electric, does it have a shroud? What temp is you thermostat?

I had a brand new fuel pump once that the line kept draining back, so it took a long time and a prime to start after sitting. I opened it and found a curled up piece of machining debris in the check valve of the fuel pump. Just because something is new doesn't mean it is working correctly.

Are all fuel lines new? It doesn't make sense if you are running 2 fuel pumps, either you have a restriction in a line somewhere and at idle the pumps will just not push the fuel past this restriction. I would remove the mechanical one, both for that matter, check all components out. Blow out lines etc. In my 58 F500 when she starts acting up I have to pull the line off the tank and blow back through it to free the debris plugging up the pick up in the tank and then I am good to go for another few hundred miles.

Have you ever had water in your gas/carburator? at open throttle water will suck through a jet but at idle a droplet of water will plug up a jet because the molecules bind together to form a bead of water and it will plug a jet. Its always something simple thats just being overlooked.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?

If I read you correctly, the pump is mounted two inches above the tank on the forward wall of the trunk?  "If" that is correct then that's what I alluded to.  Electric pumps need to be mounted at or below the bottom of the fuel tank in order to keep a good prime and push a consistant supply of fuel.  It is probably working marginally now only because of the vacuum supplied by the mechanical pump.  When the mechanical pump starts to vaporize fuel due to heat, it looses it's vacuum and the electric pump, being mounted above the fuel level , can't supply the fuel to overcome the vapor problem.  That's my theoretical WAG at it anyway.

What is this engine running for initial advance - and what sort of vacuum advance is on there? Retarded spark builds heat - at idle - if you run ported vacuum to the vacuum advance pot. That is my experience and maybe others have had the same? If I let my outfit sit at idle - and swap the vacuum pot hose between ported ....and straight manifold vacuum....the ported makes the temp climb immediately. This is taking measurements with the infared gun directly on the thermostat housing.

 
 Steve Metzger       Tucson, Arizona

No bump,it's not 2" above tank, it's about an inch or two above where the line comes out. If the tank was full it would run by gravity to the pump. The line comes out of the tank to the pump and then forward of the back wheel it goes outside the frame to the front of the car. The only think I have done is put dual exhaust on it and now there is an exhaust pipe where there used to not be one. I'll crawl under there and make sure the fuel line is nowhere near that exhaust pipe. I just thought of that when folks were asking if anything had changed. As far as things being stopped up it seems to be that would affect high power more than basically idle power. It will wind up to 5 grand and never miss a beat .. I appreciate all the thought you guys are giving me. Thanks a ton .... Oh by the way, I'm running 12 degrees initial advance with the vacuum hose plugged up.

Doing Fords for 45 years. '56 Customline Victoria

E.J. in Havana FL

When you say "with the vacuum hose plugged up" - is that simply for a test? or are you running a full mechanical advance curve and no vacuum at any time? A tuned full mechanical advance curve can deliver snappy performance as you described when the rev's go up. But when you get off the gas and go to idle - you only get the initial.

 
 Steve Metzger       Tucson, Arizona