isnt the flow rate on in line and in tank the same?? There are lots of people making lots more power than what you are on the in line walbros.... You never answered my question of what you meant by "not working good". All i was hinting at is if you were having problems with it not getting fuel, i highly doubt the pump was the problem
There are two versions of the Walbro 255lph pump, a normal and a high pressure version. The normal one maxes out at 60psi (good for n/a engines or mild boosted engine) and the high pressure version is good for 90psi or so and is for high boost engines. I'm not sure they sell a high pressure inline version (hence the issues noted above).
I bought the walbro about 1 yr ago. The one I bought turned out to be a low pressure version.
Through advice from Shanon...I know what to do about a high-po fuel pump when I'm ready.
The pump on my car at the time was and is a 190lph 80 max, and it does the job for now.
The car has: 35lb inject, big vam, LA2 ecu. Mildly prted head, ported upper and lwer intake. Ranger roller cam with adjustable cam gear set -2. Ported E-6 exhaust manfld. 3" exhaust. Front mount intercooler.
I'm not an expert, but this car has been in progress for some time. I've gotten my advice from Shanon.
I've also contacted the resource that Shanon uses regarded a external Walbro. That resource stated his GSL392 had 60 max psi(low pressure). And he didn't have a high pressure in-line(at that time), but the intank high pressure pump was available.
Just saying, I don't know eveything, but I've been on this vehicle for some time.