Hello everyone,

Have had my evo for a couple of months now and recently fuel pump is acting up. After close inspection, my mechanic has confirmed its a fake walbro so we swapped it with another fuelpump.However the current fuelpump is a 340lph one and has give me a higher fuel pressure reading at 4bar(from fuel regulator). would it do any harm to my car with the high flow fuel pump as my car is completely stock. We tried to bring it down to 3 bar but no success. Any clarifications would be much appreciated.. cheers.

 

Sounds like it's over running the regulator, if it's a stock regulator, you need to go AFPR. If it's aftermarket, and it won't adjust down, you need to find the restriction in the return line.

It's going to run richer, how much exactly I wouldn't know. A tune could compensate, but it's a band-aid.

 

i wouldnt think a 340 would cause over pressure.. but maybe it does.

 

yup, only managed to get about 240-280km for a 40litres full tank. did noticed black smoke during WOT. so, the best solution is to change back to 255lph fuel pump i reckon.

 

Did you rewired your fuel pump power source? If it is oem, then your pump should be running on 8 volts at idle.

 

Yes, my mechanic did add a relay to the fuel pump.

 

have him put it back to stock and see if that fixes your problem. You don't need to add relay until you reach 430+ whp.