Does a pump have losses due to line resistance or circuit design to flow to the return line?

My understanding is pump flow rate is rated at 3bar, but to produce this pressure at fuel rail, pump often needs to work harder due to flow resistance, which means higher pressure at the pump, ie 3.4 bar. At 3.4 bar pump is rate lower flow rate, then it becomes the problem.

Fuel pressure reg makes sure fuel rail gets to a certain pressure, so pump pressure should be the same when rail pressure is fixed.

Can anyone confirm?

using the Perth-WRX mobile app

__________________
MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport

I found a pump test online that tests many of the popular pumps including the DW65c. They give a maximum hp flowed which seems to be at a 50psi flow pressure. I dont know how this is determined but would have thought that peak hp would occur at base fuel pressure plus target boost pressure. In many cases this should be close to 63-70psi. The 65c peaked at 718hp, assuming at the crank.

If you reduced the hp figures by 30% for use with e85 then this crank figure will reduce to to 502 hp. Depending on drive line losses I would guess that the 65c will max out at around 430whp.

Have a look and share your thoughts.

Dimensionally the smallest pump in our test, this modest-sized unit surprised us by delivering big numbers. Designed to fit in vehicles like the '08-and-newer WRX/STI, BRZ, and Scion FR-S models, this 320-lph unit at 9.3 V and 50 psi flowed a respectable 249.21 lph and rated at 718.2 BHP. Marketed by DeatschWerks as the world's first 65mm bodied high-performance pump, the DW65C's turbine impeller ensures longevity and is also ethanol compatible.

Read more: Fuel Pump Shootout Part 2 - Fueling For Power

I have the aeromotive 340 in my foz its no bigger then a walbro 255 and is flowing more then enough fuel for mine at. 340hp on ethanol

using the Perth-WRX mobile app

Finally got the rev cut fixed

Car now have no cat, bigger pump, Sard fuel pressure reg, and more importantly e85!!!

Car is tuned to 1.55 bar, and made 409whp and 560wtq. On this wednesday, did a 12.33 run (not me driving), but had fuel cut issue, have to be fixed.

Attached Thumbnails

   

__________________
MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport

Car felt fast too. Sounds like an evo once on the throttle.

What was the cause of the rev cut Gordon?

Should go well into the 11's now it's sorted.

__________________
Bye bye betty blue. Hello F6.

Cam sensor, it didn't throw a code for some reason.

using the Perth-WRX mobile app

__________________
MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport

I've got the walbro 460 in mine. I was amazed how small it is for the amount it flows.
Considering I'm just pottering around doing running in kms at the moment it's also perfectly civilised.

__________________
605whp
Quarter Mile in 10.9 seconds @ 135mph /217kph
0-100 kph 3.2 seconds

Yea, walbo 450 is surprisingly quiet. But I think it draws too much current.

using the Perth-WRX mobile app

__________________
MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport