aftermarket fuel pump ??

[IMR-Merlin]

Is anyone using an aftermarket fuel pump? I am not running CIS, nor am I limited to run factory fuel lines.

The car will have a 500 hp EFI engine and I want to run the correct pump. I will be running all new lines and filters.

Anyone have a suggestion on a good in line pump?

Thanks in advance

Brendon

[jsveb]

I would use the bosch 044.
It is cheaper than oem and delivers more fuel. Used by many here on the board

[turbobrat930]

^^^^ I second that above. I was also thinking about running a Weldon pump that many turbo Chevy world run.... I called Chris at Turbokraft and had a nice chat with him. He recommended (2) 044 pumps... That will give you plenty of headroom and they are E-85 safe....

[mclaren55]

I also use twin 044's, plenty of fuel and no issues as of yet.

[IMR-Merlin]

Just out of curiosity, why not run one big pump instead of 2 044's? I will be building this system from scratch and can update the line size.

[jsveb]

Merlin, I can't answer that question, but I will tell you even though your car is apart, it will be a pain to install fuel lines that are significantly larger than the stock ones. That is if you route them as Porsche did. There is very limited space in there.

[xbmwguy]

i am about to embark on the same path , yet did not think the bosch units are e-85 friendly. i also think 2 pumps is out of line. my o2. merlin which filter and micron rate thanks frank

[spuggy]

Originally Posted by IMR-Merlin

Just out of curiosity, why not run one big pump instead of 2 044's? I will be building this system from scratch and can update the line size.

Have you found a pump with a higher spec than 044? That actually performs better? (hint: the Walbro "300 litre" pump doesn't perform anything like as well as the 044 - also rated at "300 litres" - and the difference is especially marked at higher - e.g. CIS - pressures).

I make 425 FWHP on CIS with a single 044 up front. When I go EFI, I don't see any reason at all to fit another pump. Because the pressure will drop (roughly halve) - the flow will increase correspondingly.

[mooney265]

Originally Posted by mclaren55

I also use twin 044's, plenty of fuel and no issues as of yet.

Did u modify the fuses, wiring, relays?

Sent from my MB855 using Tapatalk 2

[IMR-Merlin]

Originally Posted by spuggy

Have you found a pump with a higher spec than 044? That actually performs better? (hint: the Walbro "300 litre" pump doesn't perform anything like as well as the 044 - also rated at "300 litres" - and the difference is especially marked at higher - e.g. CIS - pressures).

I make 425 FWHP on CIS with a single 044 up front. When I go EFI, I don't see any reason at all to fit another pump. Because the pressure will drop (roughly halve) - the flow will increase correspondingly.

Are you telling me that the Bosch 044 is the high water mark for inline fuel pumps?
I would think that a high revving NASCAR engine or a 2000 HP drag car would be running a higher flow rate than a 265 lph 044.

If you are fine with the single 044, then why the redundant system with 2 pumps? Is there an issue with pump cavitation and losing pressure under max flow? I am just curious as to the benefits of 2 equal rate pumps performing the same task a 1 higher flow pump.

I am running oil lines forward for my oil tank and I could run fuel lines in a new location if it was beneficial.

Thanks for all the feedback

Brendon

[IMR-Merlin]

Originally Posted by mooney265

Did u modify the fuses, wiring, relays?

Sent from my MB855 using Tapatalk 2

I will be building my own wire harness from a hybrid between the factory harness and a painless wiring harness. The engine harness is stand alone already, so I want to clean up a lot of the old harness and update to blade fuses.

[willtel]

If you go with an 044 buy it from a reputable source and watch out for cheap ones. There have been many cases of people buying counterfeit pumps that don't perform to spec.

BOSCH 044 real and knockoffs --read this-- - RX7Club.com

[mclaren55]

Originally Posted by mooney265

Did u modify the fuses, wiring, relays?

Sent from my MB855 using Tapatalk 2

The only thing the stock fuse box is used for now are the accessories pretty much. TEC3R, custom wiring harness, different relays, etc.

There were a myriad of reasons we chose twin pumps instead of a single. Ground clearance was an issue, also I wanted redundancy built into the system in-case one pump failed. The tuning in the initial stand alone was already dialed in for twin pumps as well. Just made sense at the time.

I also have used Walbro 255's in previous projects with success as well. All up to preference I guess.

[IMR-Merlin]

Originally Posted by willtel

If you go with an 044 buy it from a reputable source and watch out for cheap ones. There have been many cases of people buying counterfeit pumps that don't perform to spec.

BOSCH 044 real and knockoffs --read this-- - RX7Club.com

Thanks I have a PM offer for a set of pumps from a Pelican member.

[Tippy]

Twin Bosch -044's here too with EFI.

[spuggy]

Originally Posted by IMR-Merlin

Are you telling me that the Bosch 044 is the high water mark for inline fuel pumps?

Do some research. For the price point, it probably is - the JDM tuner guys seem to think so. One shop benched Walbros against 044's and published graphs. The 044 flowed more fuel at higher pressures than the Walbro was capable of ever, under any circumstance - and drew less current.

It's factory fitment on GT3's. It was factory (albeit a different factory) fitment on 500+HP Cosworth's. The WRC rally guys use them. It's widely used in motorsport.

I would think that a high revving NASCAR engine or a 2000 HP drag car would be running a higher flow rate than a 265 lph 044.

LOL. Then go buy a fuel pump for a 2000HP drag car, if it makes you feel happier.

If you are fine with the single 044, then why the redundant system with 2 pumps? Is there an issue with pump cavitation and losing pressure under max flow? I am just curious as to the benefits of 2 equal rate pumps performing the same task a 1 higher flow pump.

The reason for two fuel pumps is flow goes down as the pressure requirement goes up. CIS wants a system pressure of ~6-8 bar, depending on year.

Using two lower spec fuel pumps - as they factory did - enables them to meet both requirements.

But EFI more typically runs at 3 bar than 8 bar.

Fitting two pumps - in series - if one will do the job increases, not reduces, the chance of failure.

What happens if a pump dies? Exactly the same as the overboost protection kicking in. You have a pump forcing gas through a dead pump. Or a dead pump at the tank restricting flow to the good pump. You're in limp home mode.

The WRC rally guys and the endurance racers run multiple 044's - but they're in parallel. Because a single pump will do the job, and the extras are there for redundancy.

[Tippy]

Are you telling me that the Bosch 044 is the high water mark for inline fuel pumps?

I would think that a high revving NASCAR engine or a 2000 HP drag car would be running a higher flow rate than a 265 lph 044.

IIRC, they use mechanical belt driven fuel pumps.

Running pumps in series increases volume and helps maintain pressure at a higher demand. They're essentially helping each other.

[IMR-Merlin]

Originally Posted by spuggy

Fitting two pumps - in series - if one will do the job increases, not reduces, the chance of failure.

What happens if a pump dies? Exactly the same as the overboost protection kicking in. You have a pump forcing gas through a dead pump. Or a dead pump at the tank restricting flow to the good pump. You're in limp home mode.

Or the car goes lean and you toast your engine.

I remember that VW had some issues with tank pumps going bad in their Golf MKII cars. The cars would go lean and die. I would hate to see the AFR when that happened under boost. I guess a fuel gauge with a low pressure warning light would remedy that though.

Thanks again for the input.

[IMR-Merlin]

Originally Posted by Tippy

IIRC, they use mechanical belt driven fuel pumps.

Running pumps in series increases volume and helps maintain pressure at a higher demand. They're essentially helping each other.

Not the NASCAR Grand National Series cars that I worked on. But that was many moons ago.

[TurboKraft]

There are electric fuel pumps with greater flow, but they are expensive, or noisy as hell (Aeromotive)!
Put an -044 inside the stock 964/993 rubber housing and it's dead silent, reliable.

In-tank application: -040.