Originally posted by kupcar
Merv- I know the 044 is he choice of high hp tuners. I am just wondering if I could just hook up an 044 with the stock pump up front. I'm sure they have different flow rates and operating psi. I'm guessing the 044 flows more with higher psi, because it can support 650 hp. Would this combo work???????Anyone?????? Thanks, Jeff
I don't think that's a good idea. That is how my pump setup is at the moment (stock in front, 044 in rear) and my 044 is sucking too fast for the stock one to keep up so my engine is cutting out from loss of fuel pressure under heavy load. One 044 is good for around the 600-700hp level, so technically a single 044 will be good for almost everyone here. If anything, put the stock one in the rear and 044 up front. Personally, I'd just find some fittings or a pipe to eliminate the rear pump and put the 044 up front.
The Bosch 044 can handle up to something like 100+psi, and I believe it is rated at 200lph @ 5bar (72.5psi), 330lph @ ~3.8bar (55psi). Here's a comparison pic of the Walbro 255 and 044:
Here's a flow chart:
The 044 inlet is M18 x 1.5mm and outlet is M12 x 1.5mm. Anyways, just figured I post all the info I've found as there doesn't seem to be too much about the 044 out there. This is the cheapest place I've found 044's for: Jay Racing
Does anyone know if there is any real difference in the pumps on 930's of different years? Kupcar, I recently bought a '80-83 930 front pump for my Carrera. I ended up only using it for a few days and went back to my old setup so it's relatively new. If the pump will work for you, it's yours for $150 shipped.
If you're not interested, you might as well upgrade to a 044 as you'd save money over stock and have more than enough room for the future.
Just FYI, Walbro pumps are designed to operate at lower pressures. I believe they are rated at around ~3bar, though I think they might be able to handle around 4-5bar reliably. There is a specific "high pressure" Walbro 255 model in case anyone happens to be running high fuel pressure for some reason. From what I've seen, at higher pressures (like 5bar+) Walbro pumps seem to have reliability issues. I spent a lot of time researching and the 044 was one of the few pumps I could find that can handle a ton of pressure (100+psi). My ghetto Protomotive setup is running ~6.8bar (~99psi) fuel pressure as a result of the boost level and stupid rising rate fpr. Geez, I can't wait to go with a Protomotive or aftermarket MAP sensing setup so I can get an adjustable fpr and drop the pressure down to a not-so-stratospheric level!
Anyways, if anyone happens to have a similar setup and is running over 5 bar fuel pressure, keep these things in mind when considering fuel pumps. It seems that most around here are running 5 bar or less, so this won't apply for most people.