I copied this off another forum but couldn't subscribe to the thread because it was closed so I wanted to post it here for future reference
I did a little research on the Bosch pumps that are being used and this is what I found out from Bosch Motorsports and one of their US distributors.

Let me first preface this by saying that pumps flow different amounts under different conditions. Typically less voltage to the pump, higher pressure, and higher temperature means less flow out of the pump. The flow numbers and max HP approximations I am reporting are the numbers Bosch supplied for the various models and I do not have information for other pressures or voltages yet. The distributor did say that the flow and HP numbers are a little conservative.

Pump #1: Bosch 0 580 254 979

This is the pump I hear referred to as the 310 LPH pump frequently.

Bosch Rating: 165 LPH at 72.5 PSI and 13.5 V

Bosch Rating: 230 LPH at 43.5 PSI and 13.5 V

Bosch Approximate Crank HP rating at 72.5 PSI and 13.5 V: 600 HP

Best Price I Found: $219.00


Pump #2: Bosch 0 580 254 044

This is the pump I hear referred to as the 420 LPH pump frequently.

Bosch Rating: 200 LPH at 72.5 PSI and 13.5 V

Bosch Approximate Crank HP rating at 72.5 PSI and 13.5 V: 750 HP

Best Price I Found: $220.00


Pump #3: Bosch B 261 205 413

This pump is the same pump as pump #2, but this pump is flow tested and rated at 116 PSI instead of 72.5 PSI. What Bosch does is flow some of the pumps and sort them out. This pump they will guarantee to flow its rated capacity at 116 PSI instead of 72.5 PSI. Since lower peressure generally means more flow, all else equal, I think this pump will outflow pump #2 at typical working rail pressures (60 - 80 PSI) or at least maintain a high flow rate if rail pressures above 72.5 PSI are required in high boost / high HP applications.

Bosch Rating: 200 LPH at 116 PSI and 13.5 V

Bosch Approximate Crank HP rating at 116 PSI and 13.5 V: 750 HP

Best Price I Found: $382.78

A side note on pump #3 is that it is only available from a Bosch Motorsports dealer, which is different than a regular shop that sells Bosch products.

Obviously at lower pressures the pumps will flow more volume. Also, with the addition of a voltage booster, the pumps will flow more volume. Therefore, it is apparant that the pumps can support more power than the Bosch Motorsports representative indicated given more favorable conditions (less pressure and more voltage).

 

how big is this pump compared to a walbro 255 lph?

 

try this:

bosch fuel pumps

 

My new setup consists of a Bosch 040 fuel pump intank running 10an hose to a really big Russell fuel filter to a 10an x 2-8an wye block to 2-Bosch 044 fuel pumps with 1 running to each fuel rail and a boost indexed regulator at the front with a 10an return line.I'm running 60lb[42.5] injectors at 75psi,which raises their rating to about 83lbs.

 

that sounds sweet, did you happen to take any pictures of the new setup?
How exactly did you fit the 040 in the stock fuel tank/bucket?

 

I did away with the bucket,on a Tahoe the fuel pump is mounted at the rear of the fuel tank and the intake for the 040 is about 1/2" from the bottom of the tank.I'll try to find some pictures.

 

that would be awesome bro, thank you

 

here's some pics of bosch setups I've saved: