Inline electric fuel pump flow rate

[qkcuda]

I replaced my mechanical fuel pump with an inline electric pump after a pushrod failure. The Carter P60430 pump I used is rated at 25 gph. If I floor it from a standing start I seem to be starving for fuel half way through second gear. I see the Edelbrock 17301 is rated at 38 gph. That is a 50% increase in flow so on paper it should work, but I don't want to waste my money if it won't solve my problem. Does anyone have any experience or suggestions? FYI it is a 400 big block that made 340 hp on the dyno, but I have just swapped to Edelbrock heads and 1.6 rockers, so it may be up to 50 hp more.

 

[33 IMP]

I'd plumb in a fuel pressure gauge that I could see while driving, (temporarily is fine, outside the passenger compartment), and see if you have pressure.
But, I have had fuel pressure gauges on all my cars.
If you don't have a gauge, for the cost of the gauge and fuel line, you might as well invest in a better pump.
The smallest pump I have on my performance cars is 130 gals/hrs.
25 gph is TINY!

 

[Aron Gleason]

I 2nd imps comment and say at least get a holley blue pump with a regulator. And you can add a small fuel pressure gauge inline close to the carburetor if anything.

 

[Fran B]

Any chance of a dirty fuel sock? Did you have enough gas in the tank.

 

[MoparLeo]

You need volume. What size is the fuel line in the sending unit inside the tank all the way to the carb ? 3/8".
and the fuel pump needs to be installed in the proper location. As close to the tank as possible and below the level of the tank if possible. It should also be connected to a toggle switch so you can manually turn it off if needed.
Also fuel pressure regulator and pressure gauge as already recommended.

 

[qkcuda]

Thanks for all of the replies. I am running the stock 5/16 sender and fuel line. The sock is new and the tank is 3/4 full. The pump has worked fine until the last modifications. Near as I can determine the Carter electric on my old car flowed 50 gph and supplied 600 hp. I think I am going to go with the Edelbrock pump so I can try and have it ready to take it down the track next weekend.

 

[Fran B]

Carter has a 72gph or had one. Google Search

 

[GTXDAN]

Here is exact same pump as Carter with same part #P4389 on Amzn for $57.

https://www.amazon.com/dp/B0G6K2NBHK?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

 

[qkcuda]

That looks like the Carter that was on my old car, but it was noisy. I ordered the Edelbrock pump to get me going for now. It won't require any extra plumbing or wiring and it has to be better than the one I have.

 

[Geoff 2]

Yes, not enough delivery volume. Pumps are usually quoted in free flow. No lines or filter attached, so the actual fuel delivered is usually less than the quoted number. A 450 hp engine consumes about 38 gph with the correct a/f ratio. The best elec pump for your engine is the Carter 4594, 72 gph, lasts forever.

 

[451Mopar]

That is sort of a small pump, but where and how is it mounted?
Mount it as close to the fuel tank as you can as pumps don't suck fuel well. level or below tank will help the fuel siphon out of the tank to the pump.
Make sure the tank is vented.
You can test the pump by putting a "T" fitting on the outlet line and hook up a pressure gauge to one port, then on the other port with rubber fuel line restrict the outlet until the pressure gauge shows the regulated fuel pressure and then time how long it takes to fill a known volume. I usually use a 5-gallon fuel jug, but usually testing higher volume pumps.
Anyhow, then you can actually see and calculate how much fuel is really flowing.
Stuff like a bad pickup sock, non-venting tank, clogged fuel line or pickup, or small / pinhole air leak in the tank to pump line will result in way lower fuel volume than the pump is rated.

 

[qkcuda]

This is the current pump setup. The Edelbrock pump should occupy the same space with just a bracket to fab. If it doesn't work out I am out $100. This is a cruiser not a race car. I am interested in taking it down the track at least once to test my modifications. With 2.94 gears, all I need it to do is pull cleanly through second gear.

 

[Fran B]

That looks like the Carter that was on my old car, but it was noisy. I ordered the Edelbrock pump to get me going for now. It won't require any extra plumbing or wiring and it has to be better than the one I have.

Yes it's noisy.

 

[qkcuda]

I won't have the new pump for a couple of days. I went out and found some sheetmetal and began to fab a bracket to hold it in place. I can't trim any further until I have the actual pump and decide if it will mount on the side or the bottom, but it's a start. I'd like to nestle it up in the recess above the existing fuel filter, and have it act as a stone guard as well.

 

[qkcuda]

I thought I should update this thread. The pump arrived on Friday and I began installing it as soon as I got home. I scrapped the bracket idea and bolted it directly to the seat support. I had some trouble getting it to prime, but once I bled the system it was fine. I checked for leaks and made sure it would start and called it a night. I headed out at 8 the next morning and it ran great on the 1.5 hour drive to the race track. I only got to make one time trial due to off and on showers, but it pulled strongly right through first and second. With 2.94 gears I just shifted into third at the finish line. For what it's worth I ran a 15.11 at 91 mph, which is a major improvement over the original 361.

 

[Fran B]

Your testing to race,

times are secondary. Fuel pump on my Dodge is kinda high. I need to prime the pump if it sits, I pull a fuel line and use a bulb pump. Wouldn't mount it under car. Post your results.

 

[qkcuda]

Mine says gravity feed, must be mounted below the bottom of the tank. I started before the pump and loosened every hose connecion to make sure fuel was flowing. Maybe there was an air lock, anyway it works just fine now.