"best" fuel pump to use as a lifter pump

[Toilet Duck]

Morning all,

Short version of question as per title, here is long version......

I have converted my non-return to tank OE fuel system to a return to tank system along with other changes/upgrades due to additional power and increase in fuel supply requirements. Originally, the system used a single in tank pump to supply the (non return) fuel rail via a filter and mechanical pressure regulator. I have since changed this so that the standard in tank pump is now acting as a "lifter" pump and feeds a swirl pot, then goes to a Sytec Bullet filter, then feeds a Bosch 044 pump, then feeds an Injector Dynamics F750 fuel filter, then feeds a larger fuel rail with a return port and ID1050 injectors, the fuel rail return port feeds an adjustable pressure regulator which bleeds off excess fuel back to the swirl pot, which in turn feeds back to the petrol tank when it is full.

I have removed the fuel tank and am currently having it baffled and want to ditch the OE in tank pump and replace with an external lifter pump. I want to do this because the engine has to come out to get access to the fuel tank/pump so any future problems with the lifter pump will be easier to work on. Also, I have no idea how good the "standard" fuel pump is, it is a bit of an unknown quantity. However, due to packaging etc it is not possible to modify the tank to allow a connection on the bottom of the fuel tank to feed the lifter pump, it has to be drawn out via the top of the tank with a hard pipe going from top of tank to bottom internally and a dash fitting welded on the top to allow hose connection.

It has been suggested I use a "facet red top" pump which I believe is this https://www.merlinmotorsport.co.uk/p/facet-red-top... I would appreciate any help/recommendations as to whether this is the "best" choice from the resident experts on here.

Cheers

[stevieturbo]

2 external pumps always seems messier when in-tank pumps can be used. Although if you're going to the trouble of re-designing the tank....design it so it needs no external swirl tanks or multiple pumps.
Obviously access and maintenance are valid reasons for moving to external though. But with that tank redesign, 'd have wanted to get rid of the swirl altogether, unless it's a serious track performer.

Lift pump needs to be capable of providing all the fuel the engine can consume at any time, and IMO it should also be capable of outflowing the main high pressure pump so ideally you could negate a need to return fuel to a small swirl tank from the rails.
Although a lesser pump and returning fuel to the swirl and then main tank is more common, and will lead to hotter fuel in the swirl tank. Although actual usage etc etc will dictate whether this is much of a concern.

Those stty baby Sytec filters are wholly inappropriate for the supply side of a 044, unless there is a pretty big pump forcing the fuel through.

I cant imagine how a "200hp" pump, would ever be deemed sensible or suitable as a lift pump when supplying a 700hp pump.

Something is seriously mismatched there.

[Toilet Duck]

stevieturbo said:

2 external pumps always seems messier when in-tank pumps can be used. Although if you're going to the trouble of re-designing the tank....design it so it needs no external swirl tanks or multiple pumps.
Obviously access and maintenance are valid reasons for moving to external though. But with that tank redesign, 'd have wanted to get rid of the swirl altogether, unless it's a serious track performer.

Lift pump needs to be capable of providing all the fuel the engine can consume at any time, and IMO it should also be capable of outflowing the main high pressure pump so ideally you could negate a need to return fuel to a small swirl tank from the rails.
Although a lesser pump and returning fuel to the swirl and then main tank is more common, and will lead to hotter fuel in the swirl tank. Although actual usage etc etc will dictate whether this is much of a concern.

Those stty baby Sytec filters are wholly inappropriate for the supply side of a 044, unless there is a pretty big pump forcing the fuel through.

I cant imagine how a "200hp" pump, would ever be deemed sensible or suitable as a lift pump when supplying a 700hp pump.

Something is seriously mismatched there.

Thanks for the response! If I knew earlier on what I know now, I would have had a new tank built from scratch with a decent in tank pump and not bothered with the swirl pot etc.

However, I went with the swirl pot and external Bosch 044 pump earlier in the year as it was easier and I believed would solve fuel surge issues in the tank. However, heavy track use still causes fuel surge issues unless the fuel level in the tank is kept higher than what you would realistically expect. When I removed the stty OE in tank pump the pick up point seems quite high relative to the bottom of the tank.

Having removed and taken my existing tank to a fabricator (http://www.proalloy.co.uk/), it was decided that seeing as I had already bought, fitted and installed the swirl pot/044 pump etc etc, the most economical way to proceed was to modify the existing tank by cutting open and fitting a collector box and stuffing with foam, and fitting new AN fittings with a hard fuel pipe directed into the collector box.

You mention that the Sytec filters are inappropriate, what would you recommend instead then? According to the specs (https://www.merlinmotorsport.co.uk/p/sytec-bullet-fuel-filter-with-6jic-tails-inj-filt-f1) they claim it's fine to use either before the fuel pump (as a pre-filter in my case) as long as you install a 55 micron element. If you believe the Sytec filter could be acting as a bottle neck then I'll happily replace it.

The issue I'm getting is that on track when the fuel gets lowish and I'm on lots of bends the power drops off. If i get off the gas for a while power restores and I can can go full chat again but if I continue for any length of time the problem comes back so I just come in and refuel. When the tank is full I don't experience any issues, so I believe its a fuel surge issue with fuel sloshing around in the tank and away from the current pick up point.

The car is an Ariel Atom with a Honda K20 and a TVS 1320 supercharger mapped to 350bhp at the wheels on a rototest hub mounted dyno, so around 400bhp at the crank. The actual fuel tank isn't big, maybe gets 30- 35 litres in it and I doubt the shape is ideal as it's all compromised by the surrounding chassis rails etc.

I know someone with a circa 500bhp (crank) atom running the same setup i.e. swirl pot and baffled tank with a red top pump acting as a lifter and a bosch 044 pump as a "main" pump and his set up runs fine, hence why I initially went down the same route but without the baffled tank to start.

I know the 044 pump is probably over specced for 400bhp but I would sooner have plenty of headroom rather than using stuff that's on the "limit"

If you believe the red top pump I linked to isn't "sensible or suitable", what would you recommend?

Again, thanks for your reply

[tapkaJohnD]

Duck,
I read what you say about having already gone with the swirl pot etc, but have you considered a Holley Hydramat? See: https://www.holley.com/search/?q=hydramat

I'm in a similar position, except I never had an intank pump, just a system that cut out on bends, which a swirl pot has cured. Then, I went with a Facet 'coz I had one on the shelf. Now, because I run a wheelwell, cylindrical tank, I would consider a Hydramat Cross. https://www.holley.com/products/fuel_systems/hydra...

John

[stevieturbo]

Hydramat is cool....but bloody expensive. Not a route I'd take unless it was a last resort. And apparently they have a service life.

As for filters, any of the typical stuff, Aeromotive, Holley/Earls, Fuelab etc etc. Not mickey mouse stuff like Sytec, although at a push they'd be ok on the high pressure side.

Really for the lift pump, the original EFI pump would have been very good, or another similar efi pump. They're plentiful, quiet, reliable and at low pressures flow a lot more than at EFI pressures.
So when it was in the tank already....it makes perfect sense. Or a higher flow drop in replacement

But if you want an old type of self priming pump more akin to a carb install, these Carter pumps are good, and can be bought in a lot of different flow ratings.
This one would be a little shy in keeping up with an 044, but flow a stload more than the crappy Facet. They do them up to around 100gph though ( US gallon, ie 4 litres, ie 400 litres per hour, 044 at a base pressure of around 45psi would be in the 250-300 range depending on install, lines, wiring etc )

https://www.ebay.com/itm/Carter-Electric-Inline-Fu...

[stevieturbo]

eg, this would be fine as a pre-filter pump where you are pumping the fuel to the 044

https://www.earls.com.au/shop/earls-175-gph-billet...

With filters there are no downsides to going big ( that's a small one )

Fuelab

https://www.competitionsupplies.com/fuelab-in-line...

Aeromotive

https://www.demon-tweeks.com/uk/aeromotive-in-line...

But there are many other brands too.

Something in the range of 40-100 microns pre pump, and then 10 microns for the injectors. Some injectors can be very fussy, some less so.

[Toilet Duck]

tapkaJohnD said:

Duck,
have you considered a Holley Hydramat? See: https://www.holley.com/search/?q=hydramat

I did come across that stuff whilst googling about fuel surge etc, hadn't heard of it before. I'm sure it's amazing stuff but the hideous price put me off and also due to the fact that my existing tank would still need cutting about to get access etc, I'd rather have a collector box welded in if I'm going to the expense of having it "modified".

Stevieturbo, thank you very much for the further explanations and links etc, very much appreciated! I will look into those options and make some changes to my set up.

I'm sure this is a basic question, but why is it that the Carter pump you linked to is (I presume) suitable for "pulling" fuel up a vertical pipe welded into a tank, yet Bosch 044 pumps don't like this and need to be fed the fuel under gravity from above? What is the difference between the two pumps? Obviously "pulling" fuel up must be a key attribute of a "lifter" pump, but what actually is the difference in terms of pump design/type? I hope that makes sense?

Once again, many thanks

[GreenV8S]

Toilet Duck said:

why is it that the Carter pump you linked to is (I presume) suitable for "pulling" fuel up a vertical pipe welded into a tank, yet Bosch 044 pumps don't like this

Those are low pressure pumps. High pressure injection pumps are far more vulnerable to cavitation when there is any restriction on the supply side.

[stevieturbo]

Toilet Duck said:

I did come across that stuff whilst googling about fuel surge etc, hadn't heard of it before. I'm sure it's amazing stuff but the hideous price put me off and also due to the fact that my existing tank would still need cutting about to get access etc, I'd rather have a collector box welded in if I'm going to the expense of having it "modified".

Stevieturbo, thank you very much for the further explanations and links etc, very much appreciated! I will look into those options and make some changes to my set up.

I'm sure this is a basic question, but why is it that the Carter pump you linked to is (I presume) suitable for "pulling" fuel up a vertical pipe welded into a tank, yet Bosch 044 pumps don't like this and need to be fed the fuel under gravity from above? What is the difference between the two pumps? Obviously "pulling" fuel up must be a key attribute of a "lifter" pump, but what actually is the difference in terms of pump design/type? I hope that makes sense?

Once again, many thanks

The two are just completely different pumps. A bit like why is a Fiesta different from a Rolls Royce. They're both cars.

Almost no EFI type pump will or likes to pull fuel. They're great at making pressure though, but they dont lift. Hence they always need to either be submerged or have a good clean unrestricted gravity fed supply of fuel.

044 is like a roller cell pump, most modern EFI's are a turbo vane type pump. I think that Carter pump might be a gear pump. Older carb pumps tended to be like a diaphragm pump.

[Toilet Duck]

Thank you both for clarifying!

I've been looking into those Carter pumps and found this one: https://www.amazon.com/Carter-P4600HP-Line-Electri... there is a bit more detail listed here: https://www.jegs.com/i/Carter/180/P4600HP/10002/-1

It says it flows 100gph (so that's 378 uk litres per hour!) which is more in line with what you said about the lifter fuel pump out supplying the main fuel pump. I think I'll go for this one unless there is anything else I need to be aware of? Do they have to be mounted a "correct" way up e.g. pump bit at the bottom and in/out fuel connections at the top or vice versa etc? I've found the manufacturer site but it doesn't seem to list much detail.

Many thanks again!

[stevieturbo]

Toilet Duck said:

Thank you both for clarifying!

I've been looking into those Carter pumps and found this one: https://www.amazon.com/Carter-P4600HP-Line-Electri... there is a bit more detail listed here: https://www.jegs.com/i/Carter/180/P4600HP/10002/-1

It says it flows 100gph (so that's 378 uk litres per hour!) which is more in line with what you said about the lifter fuel pump out supplying the main fuel pump. I think I'll go for this one unless there is anything else I need to be aware of? Do they have to be mounted a "correct" way up e.g. pump bit at the bottom and in/out fuel connections at the top or vice versa etc? I've found the manufacturer site but it doesn't seem to list much detail.

Many thanks again!

The one I used years ago, I mounted as per the Jegs picture, which also indicates an arrow on the body. So it probably does need mounted that way up.

That said, I've also used the same pump in later years for emptying old fuel or heating oil tanks with it just lying on the ground.

But with the bracket supplied, the pump sort of hangs there on the rubbers as there is a little bit of noise with the pump.

If you are doing a return line back to the swirl tank as most do, then the 72gph would be perfectly fine, and it should still maintain a good flow in and out of the swirl tank back to main tank too to keep fuel cool
And it's a fair bit cheaper.

The 100gph would cover all options though, although maybe not necessary at present

Edited by stevieturbo on Tuesday 3rd December 21:30

[Toilet Duck]

stevieturbo said:

The one I used years ago, I mounted as per the Jegs picture, which also indicates an arrow on the body. So it probably does need mounted that way up.

That said, I've also used the same pump in later years for emptying old fuel or heating oil tanks with it just lying on the ground.

But with the bracket supplied, the pump sort of hangs there on the rubbers as there is a little bit of noise with the pump.

If you are doing a return line back to the swirl tank as most do, then the 72gph would be perfectly fine, and it should still maintain a good flow in and out of the swirl tank back to main tank too to keep fuel cool
And it's a fair bit cheaper.

The 100gph would cover all options though, although maybe not necessary at present

Edited by stevieturbo on Tuesday 3rd December 21:30

Perfect, thanks very much!

Just ordered through Amazon https://www.amazon.com/Carter-P4389-Line-Electric-...

I'm going to ditch the sytec pre-filter as well and go with one of your recommendations.

Thanks again, much appreciated