I need an electric pump, most likely Holley Red. But I like the performance and silence of the mechanical pump when I am not at the track. Could I install the electric at the rear, and wire it to a switch so that it will only run when I turn it on, and then run the mechanical all the time? I guess my question is will the mechanical be able to pull the fuel through the electric if the power is turned off, and can the electric push the fuel through the mechanical when it is turned on? Or, would I be better off with two separate systems and a quick disconnect at each end? Or, does someone have a better idea? I just don't trust electric pumps for full time use due to the occasional blown fuse, etc.
also if you have both in the same line, and switch from one to the other, even if it does work it'll make the other one work harder and it may not last.
if you did that you would have to have the regulator BEFORE the mechanical, otherwise you would put too much pressure into it and it would rupture and get gas in the oil... and that is NOT good at all..
OK, too bad. I will have to learn to trust the electric pump. I got the Holley "blue" 110 gph pump, and will go put it on now. It has a regulator, so I can keep it controlled to 6 psi. If the 110gph pump really only puts out 70gph at 9 psi, can I safely estimate 90 gph at 6 psi? Or does it work like that? Well, on the positive side, I can lose the big old mechanical pump and get to my oil filter much easier now.
As far as reliability goes I have had my holley AT LEAST 15 years. No problems, not even a blown fuse!
i run the electric on my high boy. been through some real abuse and its still holding up good after 5 years.
Can I turn that thing at the bottom of the tank that has the fuel level guage and the nipple coming out of the bottom of the tank? I loosened it up and tried, but it wouldn't move. I figure the sending unit is firmly attached, so it has to be in just like it is. I ask because I mounted my pump just behing that area on the inside of the frame rail, and I have to come out of that bent tube and hang a 180 toward the rear of the car to get to the pump. As it is now, I will have to do a 12" long loop going up and around and back to the pump, in order to not have it kink. As soon as I hook this up, it is ready to test. I hooked it up to the same relay that I use to run my electric fan so it only comes on when the key is turned to "start". So, I can leave the key on "on" and it won't start spinning until I tap "start".
scoop, no can turn...it has a notch to position it so the pickup is to the bottom of the tank...frank...
Would it not turn back off when you let off start and the key goes back to on? BTW: you probably trust an electric pump everyday in whatever you drive daily.
The relay simply holds the current back until something triggers it, then it switches the current on until you turn off the car. So, when I turn "on" lights and radio (if I had one) would work. Then "start" engages the starter, and the relay, turning on the fan and pump. This pump really is kinda loud. Scared me at first. I should lose some of the noise when I get carpet in. BUT...between the pertronix (installed yesterday) and the new pump (which I have set at 6.5psi, and it doesn't budge!) the tail end is all over the place if I even give it 75% throttle at takeoff, and when 2nd gear kicks in, it is swimming all over again for about 150 feet if I don't back off the throttle (keep in mind, i have posi, so it is not just one-legging it). Plus, it gets right up to 5500 rpm with no sputtering and no loss of fuel pressure. I think I may have solved many of my problems. Will test at the track tomorrow night and, if I can get traction, I should bust into the 8s on the 1/8 (13s on the 1/4). Also, a buddy in the hood has a late 80s mustang with a double pumper Demon on it, and he can't get it to work right. I gave him my mechanical pump and my old air shocks, and he offered to swap out carbs for a week or two so he can decide if it is a carb issue or what. Then he can decide if he wants to buy an Edelbrock and I will know if I want a double pumper holley. I think he is just not running right due to not having the proper fuel pressure. So his carb should bolt right up and do it for me.
run it with the edel first then change over to the demon and see if your times change. im thinking the fuel pump change you just made is going to be a major step in the right direction. you might be able to dial a half a tenth one way or another by adjusting the rods and such, but the gas coming in fast enough is really going to be good
