So I figured its been about 10 years since I did a flow check against fuel pumps or did any research so......
Last night I made a real world bench tester. NOT super precise or scientific!
I started with a 5000cc lab beaker in 50 100 and 1000cc values
I then used a stock SR20de fuel rail with the stock FPR modified to run 50psi
Hooked up to a auto meter full sweep manual pressure gauge (100psi)
6" of rubber 5/16 line to a Z32 oem fuel filter to 3" of 5/16 rubber line to a stock s13 hard line
8" of 3/8 rubber line to the fuel pumps.
I used regular unleaded fuel and measured its temp at 45* F
I used a 12v 30amp (@ 50% duty cycle) power supply and measured voltage on a fluke DMM
I used a Allen-Bradley timed relay set to 1 min and 1 sec
I primed all pumps and it took aprox 1 sec to build head pressure and flow
I ran all pumps 5 times @ 50psi and took the average
I tested a walbro255 a R33 GTR a Z32 and a R32GTR I also have a SR20DET oem pump not sure about the year and model so I did not check it
12 volts @ 50psi The R33 flowed 3550cc/min average
12 volts @ 50psi The Walbro flowed 3100cc/min average
12 volts @ 50psi The Z32 flowed 3050cc/min
The R32 gave really odd reading and its suspect the check valve is bad..
It looks as though from what have seen and read the walbro's really take a nose dive when they are at low voltage and or high pressure. It also has no built in damper and the needle on my original gauge bounced around until I installed on from a Honda fuel rail. The R33/32 and Z32 has one built in.
I want to continue this at higher voltages (up to 16.5) and higher pressures(up to 80 or 90psi) and see what they actually run in our fuel systems
Here are a couple charts I have cant remember where I found them?
gotta go back to work so Ill post more later...........
Dec 28, 2007, 5:55 pm · #1