Fuel pump 044 or RS2 ?which is better??

[piotr]

i'm upgrading my coupe ABY to RS2 spec and i'm thinking what will be better choice-RS2 fuel pump or BOSCH 044?i was gonna buy 044 but i have done some research on forum and there is fiew people who complain about 044 being very loud.i would be greatfull for advise

[Acidburn]

044 definately, rs2's are starting to get on a bit now so worth getting a new one if your going to.

[John B]

I run an 044 and it's not loud....well you can't hear it with the 3" Pipewerx system

No seriously, it will give you more options later if you decide to upgrade further.

[Sleeper_Avant]

044, no question!

and relay + rewire your 14v feed to the pump while you are there

regards Sean.

[SteveH]

My 044 is silent, probably quieter than an old standard pump.

[piotr]

thank you very much guys.it looks like 044 is the winner.just one more question-do you think standard aby fuel pressure regulator will be ok with this pump?

[UrS4boy]

Comparison of Bosch 044 to Walbro fuel pump curves

thank you very much guys.it looks like 044 is the winner.just one more question-do you think standard aby fuel pressure regulator will be ok with this pump?

If by that, you mean the 4 Bar Fuel Pressure Regulator (FPR) that the AAN and ABY use? The answer is yes. Many after market software suppliers for "RS2" levels use a 3.0 Bar MAP sensor in the ECU and, on that basis, are able to push the boost levels to the 28 psi (relative) range (1.93 Bar) . On that basis, the fuel pump needs to supply 4 Bar *plus* the boost pressure to the fuel rail, i.e. (4 x 14.5 psi)+28 psi = 58 psi + 28 psi = 86 psi ( = 4 Bar + 1.93 Bar = 5.93 Bar). As shown in this graph, the 044 has a very flat fuel delivery curve, i.e. the rate of fuel delivery does not drop off with increasing delivery pressures very much. In comparison, many of the more common Walbro pumps, e.g. the 255, have a steep downward delivery curve.

http://www.radiumauto.com/blog-page.php?Radium-Engineering-s-Ultimate-Fuel-Pump-Test-73

[Sleeper_Avant]

it will be fine,

the whole point of the regulator is to regulate pressure in the rail to supply the injectors with the correct pressure, in your case 3bar (if im not mistaken!)

your injectors will be rated to a specific flow rate,
i.e 280 cc/ min @ 3.0 bar
315 cc/ min @ 3.8 bar
323 cc/ min @ 4.0 bar
361 cc/ min @ 5.0 bar

hope this makes sense

and please, make sure you wire in a relay and feed the pump with 14v

nice graph Dave!

[GazzaG60]

I used an in tank 044 which with the cover over the tank in the coupe was silent. I used stock lines and fpr and 620cc injectors.

fueling was really good and no issues with supply or noise.

fit the o44 in tank in the holder like the original. if its aby you need a few bits to make it fit properly.

[UrS4boy]

...fit the o44 in tank in the holder like the original. if its aby you need a few bits to make it fit properly.

What GazzaG60 is saying is the 044 Bosch Motorsport fuel pump is 60 mm in diameter. Some early S2s came with a 60 mm fuel pump basket in the fuel tank. This makes it a no brainer to upgrade from the S2 fuel pump to the 044. HOWEVER, the later S2s *AND* the C4 UrS4s and UrS6s and the RS2 all came with 43 mm diameter fuel pump in 43 mm baskets. In this case, to upgrade to an 044 (or 040) Bosch fuel pump you need to buy/find the 60 mm basket bits from an early Audi V8 or S2.

Have a look at these two photos:

Here is a 43 mm 091G fuel pump in the two-part basket:



Here is an 044 in the larger basket with the smaller 091G in the 43 mm basket in the background:

[UrS4boy]

and please, make sure you wire in a relay and feed the pump with 14v nice graph Dave!

Here is a link to my C4 Fuel Pump Relay post (adapt as needed for the B3 and B4):

http://forums.quattroworld.com/s4s6/msgs/24327.phtml

(034 now sells a plug and play C4 kit for ^^this^^)

Here is another Bosch 044 fuel pump curve showing that its flow delivery doesn't drop off dramatically until well above 7 Bar (we probably only need 6 Bar max):

[GazzaG60]

yes. its 3b housing AND FILTER FOR HOUSING. filter is different.
RS2 connector.

my pump still had to have the 3b housing modded to get it to sit right. cable ties are your friend.

the difference is massive in fuel flow.

for reference the s2 stock pump ran dry at 5k on my engine with 1.2 bar or so on the sc61. I had to cut loads of juice from the map as id been over compensating.

[piotr]

just want say THANK YOU so much guys for all your advises and photos.
Grat forum and great peaople here shering fantastic passion.Thank you !!!