[C2] electric fuel pump...
Thread Starter
Melting Slicks
Joined: Jul 2011
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From: Bornem
electric fuel pump...
it's somewhat 'dangerous' to post about this one, it's a bit controversial, still want to give it a try...
I try to reduce fuel temp as much as I can in my 64 with a crate 350/290hp in preparation for a long trip this summer through hot areas.
It's been said many times that the mechanical pump is a heath source, so I thought scrapping it and install an electric pump at the back. I have a Holley Performance 12-426 Electric Fuel Pump 25GPH Mighty Mite Series, which should be fine , and for safety I have an oil pressure switch too so the pump only runs when the engine turns.
Now the question: what are the disadvantages of using an electric pump over the mechanical pump? Anyone done it?
I try to reduce fuel temp as much as I can in my 64 with a crate 350/290hp in preparation for a long trip this summer through hot areas.
It's been said many times that the mechanical pump is a heath source, so I thought scrapping it and install an electric pump at the back. I have a Holley Performance 12-426 Electric Fuel Pump 25GPH Mighty Mite Series, which should be fine , and for safety I have an oil pressure switch too so the pump only runs when the engine turns.
Now the question: what are the disadvantages of using an electric pump over the mechanical pump? Anyone done it?
Instructor
Joined: Feb 2013
Posts: 126
Likes: 5
electric fuel pump
I have an electric fuel at the rear of my 67 but only as an axulary , I mainly use it to start the car easier after it has set for long periods to prime the carb if the mechanical pump should have a problem then I would turn on the electric pump any time I felt I needed it, I have it wired with a switch under the dash, If your mechanical pump is good I see no reason not to keep it I don't care what the temp is and also it depends on how your fuel lines are routed, away from exhaust etc.
Le Mans Master
Joined: Feb 2006
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From: Maine
it's somewhat 'dangerous' to post about this one, it's a bit controversial, still want to give it a try...
I try to reduce fuel temp as much as I can in my 64 with a crate 350/290hp in preparation for a long trip this summer through hot areas.
It's been said many times that the mechanical pump is a heath source, so I thought scrapping it and install an electric pump at the back. I have a Holley Performance 12-426 Electric Fuel Pump 25GPH Mighty Mite Series, which should be fine , and for safety I have an oil pressure switch too so the pump only runs when the engine turns.
Now the question: what are the disadvantages of using an electric pump over the mechanical pump? Anyone done it?
I try to reduce fuel temp as much as I can in my 64 with a crate 350/290hp in preparation for a long trip this summer through hot areas.
It's been said many times that the mechanical pump is a heath source, so I thought scrapping it and install an electric pump at the back. I have a Holley Performance 12-426 Electric Fuel Pump 25GPH Mighty Mite Series, which should be fine , and for safety I have an oil pressure switch too so the pump only runs when the engine turns.
Now the question: what are the disadvantages of using an electric pump over the mechanical pump? Anyone done it?
Jack
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From: Sitting in his Nowhere land Hanover Pa
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Thread Starter
Melting Slicks
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From: Bornem
Thread Starter
Melting Slicks
Joined: Jul 2011
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From: Bornem
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I have an auxillary elec pump on 3 cars: 56 Vette, 70 Chevelle, 76 Cutlass, each has a toggle switch under the dash.
The ONLY time I ever use it on the 56 is when I antickpate spinning the SB400 with FI above 5500.
The Chevelle (SB400) and Cutlass (W30 455) both have Q-jets. Under WOT, both will run out of gas because the mechanical pump won't supply enough gas. But with the elec pump on, they never starve. Q-jets have small fuel bowls and are not good for high, or extended rpm's with a mechanical pump.
The ONLY time I ever use it on the 56 is when I antickpate spinning the SB400 with FI above 5500.
The Chevelle (SB400) and Cutlass (W30 455) both have Q-jets. Under WOT, both will run out of gas because the mechanical pump won't supply enough gas. But with the elec pump on, they never starve. Q-jets have small fuel bowls and are not good for high, or extended rpm's with a mechanical pump.
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Army
I'm considering a booster pump to deal with vapor lock in Orlando on hot days..
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except that I use electric exclusively, after all, all new cars do. I have been dealing with poor gas and vapor lock in AZ. for 20 years now with both BB and SB C2s and can tell you it is a must AND a return line is often necessary as well. If you are running headers you better be careful about where your fuel lines are in relationship also. You guys may get away with running a mechanical pump in cooler climates but until you have lived where I have lived please don't try and sell me 50 year old Cool-Aid that worked when we had better gas.
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From: Sitting in his Nowhere land Hanover Pa
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I never had your better gas so I don’t know any better and of the 15 years I have been driving carbed cars I only had a problem once in my Chevelle two years ago when I took it out in July doing a heat wave of 105. The car ran but it wasn’t happy. Never had problem since though.
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Thread Starter
Melting Slicks
Joined: Jul 2011
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From: Bornem
EXACTLY! except that I use electric exclusively, after all, all new cars do. I have been dealing with poor gas and vapor lock in AZ. for 20 years now with both BB and SB C2s and can tell you it is a must AND a return line is often necessary as well. If you are running headers you better be careful about where your fuel lines are in relationship also. You guys may get away with running a mechanical pump in cooler climates but until you have lived where I have lived please don't try and sell me 50 year old Cool-Aid that worked when we had better gas.
except that I use electric exclusively, after all, all new cars do. I have been dealing with poor gas and vapor lock in AZ. for 20 years now with both BB and SB C2s and can tell you it is a must AND a return line is often necessary as well. If you are running headers you better be careful about where your fuel lines are in relationship also. You guys may get away with running a mechanical pump in cooler climates but until you have lived where I have lived please don't try and sell me 50 year old Cool-Aid that worked when we had better gas.
Racer
Joined: Dec 2010
Posts: 254
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From: iroquois ontario
Electric pup,
I run a Holley blue pump out back. You should install a fuel pressure regulator set between 5 or 6 pressure and isolate pump with rubber type washers where attached to rear frame area. Also a relay is required when wiring up. I use my pump switch also as a theft deterrent as it hidden under the dash. Remove mech pump and buy block off plate.
Works for me .
Works for me .
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Those cars are long gone. If you are talking about the return line to the tank it is pretty simple. Order the pre-bent fuel return line for cars that came with them from the factory from one of the companies that sell repo fuel lines. 1968 hipo big blocks had them and the frame is basically the same as the C2s. You will have to put a hose bib on the fuel sending unit to get the returned fuel back in the tank. You will need some type of restrictor in the system to limit how much fuel is returned. There a couple of ways to do it. I have heard some shops refer to the orfice as a "pill" but probably the simplest way to do it is in the fuel filter which is discussed in the link below that is set up for this with a restrictor orfice. Make sure the fuel lines are routed as far away from exhaust as possible. Electric fuel pumps are designed to push not pull so make sure your fuel pump is located as close as possible to the tank. You want fuel to be pressurized all the way (as close as you can) to the carb to keep it from percolating in the line.
https://www.corvetteforum.com/forums...post1596502555
https://www.corvetteforum.com/forums...post1596502555
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Army
I wish I had a $5 bill for every old car that got traded into my Dad's used car lot with clothespins clipped along the carb fuel line (a mythical vapor lock fix) or chokes coat-hangered open, etc..
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From: Sitting in his Nowhere land Hanover Pa
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Keith - I know you're a lot younger than most of us, but don't believe all the stories about how these old cars ran perfectly back in the 60s. They didn't...there were plenty of cars broken down alongside the road with overheating problems, stuck floats, vapor lock, you-name-it.
I wish I had a $5 bill for every old car that got traded into my Dad's used car lot with clothespins clipped along the carb fuel line (a mythical vapor lock fix) or chokes coat-hangered open, etc..
I wish I had a $5 bill for every old car that got traded into my Dad's used car lot with clothespins clipped along the carb fuel line (a mythical vapor lock fix) or chokes coat-hangered open, etc..
