schpiel

If I am using this fuel pump that I was previously using on a built motor, on a stock b18b, is it possible it can be causing my car to run rich. I am using a stock, non-adjustable FPR. I didn't think it would matter, but I am now wondering. Any Help? Thanks!

hotrod99

Quote, originally posted by 00Red_SiR »
What happens in a fuel system is that a pump will pump what it's rated at. So a 255Lph pump will flow 255 liters per hour at idle all the way up to WOT, your engine will only use the required amount of fuel and send the rest of the fuel back to the tank through the return line. Because a 255 lph pump will flow SIGNIFICANTLY more fuel than the stock pump does, it tends to overwhelm the stock fuel pressure regulator/return line and therefore the fuel pressure increases because it can't bleed off the excess fuel fast enough. An aftermarket adjustable FPR will help dial the pressure down to the proper level.

Using a pump capable of flowing this amount of fuel should not be used unless you will be running boost period. A stock B series pump can handle up to 300 hp so unless you plan on going boost for sure...sell that pump and spend your money on something more practical and worthwhile.

OMGWTFBBQ!

I have been running a walbro 255lph pump on my all stock Type R for 3 months now, I ran it for over a year on my single cam. Both NA, never had a problem with either of them.

slvrcvc93

I had a 255 in my car and I ran it for a while 2 then I started going through a full tank of gas every 3 days.... yes 3 days the diaphragm in the stock regulator is made of plastic it will break eventually then it wont regulate the fuel flow i believe the stock pressure is 28-35 the 255 can flow at about 65-70 which is about double but everyone experience is different.

OMGWTFBBQ!

Well if the OP is worried about it, I have a universal fuel pressure regulator for sale in my sig

schpiel

switching out fruel pumps tomorrow with a buddy...he is about to go boost anyway. I'll see what happens tomorrow...we're hitting the junkyard, so I am gonna try and grab a FPR just incase I already dicked mine up!

B16B_coupe

my friend is having trouble with his, he has a ls in a 90 civic hatch and the fuel was poring into the cylinders we have to suck it all out and hope to god it didn't hydro-lock, We need a FPR bad