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-   -   Electric fuel pump (https://forums.maxperformanceinc.com/forums/showthread.php?t=883947)

Goatracer1 01-23-2026 10:28 PM

Electric fuel pump
 
I am looking for your ideas for an electric fuel pump. The car is a totally stock 389 1962 Bonneville. I don't need a racing fuel pump. I want to get rid of the mechanical pump. It makes too much pressure. Besides the car is parked a week or 2 without being started and requires a lot of cranking to get fuel to carb. I've had electric pumps in the past and they have been very noisy. Does anyone sell a universal in tank pump for a carbureted engine? Thanks for your time.

65 Lamnas 01-23-2026 11:40 PM

I'm not sure anybody makes what you're looking for. I get the feeling you don't want to spend much $$, but maybe I'm wrong.

If you go with an external electric pump, it's gonna be a bit noisy. Even if you mount it on rubber iso-mounts or otherwise isolate it. It's just the nature of the design of that style pump. the upside is the pump can be had for as cheap as $100.

If you want in-tank, that's a bit more of a job and expensive. But it won't be nearly as noisy. The kind I'm thinking of is likely over $500 for the kit.

Pick your poison.

Goatracer1 01-24-2026 12:20 AM

Anyone install an electric pump from a late 1970's or early 1980's car that was mounted in the tank? A 1978 305 Chevy Monza had a carb and an in tank pump as part of the sending unit. I was thinking I could shorten the present fuel pickup tube and install the pump and screen in it's place

GOAT8U2 01-24-2026 01:23 AM

If on a budget, EFI tank and basic 255 Walbro or DW300 and you won't hear much over the exhaust.

https://www.tanksinc.com/index.cfm/p...cat/cat128.htm

tstroud 01-24-2026 08:44 AM

Here is a conversion kit. You will need a fuel pressure regulator also.
https://www.tanksinc.com/index.cfm/p...prod/prd84.htm

Formulajones 01-24-2026 10:13 AM

As posted you have several in tank options. Tanks inc sells a universal in tank setup, Holley/Aeromotive has one. Shop around and pick your price point. They can be adapted to your tank. I didnt look but tanks likely doesn't offer a baffled efi style tank for a Bonneville anyway.

Pump in the tank is definitely the way to go. For what you're doing a little 190 lph would get it done but most just use a 255.

HWYSTR455 01-24-2026 10:56 AM

Sadly, no one makes a tank for that body that is ready for a 6-bolt pump assembly, and you would have to have a flange welded in. Since the pump assembly is higher than the OE lines, you would most likely need a recessed flange. Places make them, but it's more extensive work.

Once you convert to an in-tank pump module, you lose the float assembly, so you would also have to have a 5-bolt flange welded in.

Most radiator shops can do gas tank work, but most won't weld/braze on a tank that has had gas in it, unless it's been 'cleaned'. Thankfully, a regular replacement tank is available for your body. If you're going to go thru the cost of conversion, a new tank makes sense.

Pump assemblies, that 'trough' 'baffle' is not effective at all, and you could suffer from fuel starvation. Might not be as big an issue with a carb, but it you ever did want to go to a tbi type EFI, it's near worthless. The ones that have a 'bucket' work better, like these:

https://www.efihardware.com/products...ord-ba-fpv-mra

Those are 8-bolt, so when you shop for a flange, keep that in mind, it would be like these:

https://www.rickstanks.com/product/pn-26002

Nice thing about the 8-bolt flange is you can use OE type replacement pump modules.

Add that all up and you'd be better off going to a custom tank, like one from Rock Valley, Rick's, or similar.

You WANT a regulator, and it would be best to go to a bypass type. Which means you would have to run a return line. Since the type of pumps you would need to use generally move a lot of return fuel in a carb app, the line should be 1/2", and only maybe would a 3/8" line work. So no using the original vapor lines for a return.

An external pump is the least expensive route, and there are ones that are quiet. But, it's best to use a bypass regulator with those as well, and it would be best to 1/2" lines for feed & return.

A sump would be best in that case, which isn't expensive, but the same install notes above apply. You can try it without the sump to start, see how it works, and go from there.

External pump suggestions would be the geroator type since they tend to be the quietest. The ones that are based off in tank pumps have a higher failure rate when used as an external, and the 'traditional' external pumps have become kind of expensive. I've personally used the Holley HP150s, and it would be the one that I would suggest:

https://www.holley.com/products/fuel...s/parts/12-150

Finally, you could run a regulator after the mech pump, or, you could reach out to Paul Spotts, he has tested and verified fuel psi of all the available mech pumps, and has the best info on brands and types.


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Jay S 01-24-2026 11:37 AM

Quote:

Originally Posted by Goatracer1 (Post 6601049)
Anyone install an electric pump from a late 1970's or early 1980's car that was mounted in the tank? A 1978 305 Chevy Monza had a carb and an in tank pump as part of the sending unit. I was thinking I could shorten the present fuel pickup tube and install the pump and screen in it's place

I have heard of that getting retrofitted into a custom intank set up. They shortened the suction line in the tank so the suction sock was pulling from the bottom of the tank. Then used a low pressure in tank electric up from something in the early 80s. There were some smaller intank electric pumps designed for application to feed small carburetors. They rigged up electric bulkhead fitting for the wiring.

I’ve eliminate mechanical pumps on stock engines using a self priming diagram pump a few times. To make it work correctly all the time it needs a pressure regulator with a return line. Otherwise the diaphragm pump will have a difficult time to keep consistent fuel pressure and occasionally push’s fuel past the needle and seat.

Goatracer1 01-24-2026 01:18 PM

I researched several OEM in tank pumps and the one I narrowed it down to was the 1978 Monza 305V8 pump. Only problem is it is too big in diameter to fit through the sending unit hole. This is beginning to look like more trouble than it's worth. Maybe I will just add a regulator to the existing pump and live with the long crank times. Thanks to everybody who answered.

HWYSTR455 01-24-2026 01:47 PM

Here's one of Spott's posts on FB denoting the high psi issue and to use the Carter dual diaphragm one instead:

https://www.facebook.com/share/p/1FmoxjpGfg/

A post made someone else in that thread mentions the Delphi AMF0100 as one that has proper psi.

As I mentioned, if you call, he may be able to source a good one or point you in the right direction.


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mgarblik 01-24-2026 03:36 PM

If your looking for a low cost solution, an in-line external fuel pump of the "solenoid" design would do the trick. They kind of look like an old canister in-line fuel filter with 2 wires coming out of it. Easy to frame mount and with some simple rubber isolators, pretty quiet. Summit Racing has 368 different listings for these type pumps. $17.00-200.00. I would look for about 4-6 PSI and 30 or so GPM. It looked like $50-80 would buy a name brand pump like Edelbrock or Carter. If your set on going the in-tank route, maybe you can modify a 1971-1976 Vega fuel pump. They were low pressure for a carb. application.

steve25 01-24-2026 06:18 PM

Your mechanic pumps over pressure and it’s noise you say it makes is likely related I gotta say.

jerry455 01-24-2026 07:43 PM

They also used fuel tank mounted low pressure pumps in the mid 80's carbureted Camaros and Caprices for a vapor lock problem. You might be able to modify the sender for that pump.

HWYSTR455 01-24-2026 11:34 PM

Quote:

Originally Posted by steve25 (Post 6601157)
Your mechanic pumps over pressure and it’s noise you say it makes is likely related I gotta say.

Spotts says some of the arms/levers are not hardened properly and they make noise.

.

HWYSTR455 01-24-2026 11:36 PM

Quote:

Originally Posted by mgarblik (Post 6601138)
If your looking for a low cost solution, an in-line external fuel pump of the "solenoid" design would do the trick. They kind of look like an old canister in-line fuel filter with 2 wires coming out of it. Easy to frame mount and with some simple rubber isolators, pretty quiet. Summit Racing has 368 different listings for these type pumps. $17.00-200.00. I would look for about 4-6 PSI and 30 or so GPM. It looked like $50-80 would buy a name brand pump like Edelbrock or Carter. If your set on going the in-tank route, maybe you can modify a 1971-1976 Vega fuel pump. They were low pressure for a carb. application.

If this is done then you would have to bypass the mechanical pump.


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Jack Gifford 01-25-2026 12:08 AM

I've been using Facet inline pumps for at least 60 years- since they were not transistorized! They are around $75 now. The 32 GPH ones are available in at least a couple of pressure ratings- I've used the 1.5-4.0 PSI ones for all sorts of vehicles from 4 HP Kohlers on up to 389 Pontiacs. They are very quiet. I've got a pair of them in parallel on the Pontiac Tri-Power in my GMC, mounted on rubber on a frame rail and they can barely be heard even with the engine stopped.

grivera 01-25-2026 01:53 AM

This seems like a good candidate for one of the RobbMC power surge tanks that you place in the engine compartment.

Squidward 01-25-2026 05:32 AM

I am actually considering going from an in-tank pump to an external pump. I would still retain my external bypass regulator. I run 6an in and out. I did a retrofit kit from FiTech, which has you cut a hole in the tank and install a bolt in flange.

I just don't want to drop a gas tank to replace a pump. Firebirds have a short rubber filler neck connector that doesn't like to be disturbed. Ever.

Universal 255 lph kit:
https://fitechefi.com/product/50014-...600-hp-module/

Decent kit, but 1967 F body gas tank is soooo shallow it barely fit. But your application might be a breeze.

You could pair that with a bypass return regulator to do your carbureted or injected bidding. Once upon a time I found a regulator that could swap springs to do either carb or efi pressure.

Formulajones 01-25-2026 08:17 AM

Just put a door in the trunk. Quick and simple. I can change a pump with the tank full in 10-15 minutes.

Squidward 01-25-2026 08:26 AM

Quote:

Originally Posted by Formulajones (Post 6601229)
Just put a door in the trunk. Quick and simple. I can change a pump with the tank full in 10-15 minutes.

True. But how will I hold in all the water that leaks past the trunk seal?:p


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