Originally Posted by RealStreet

We have seen a few cases already reported of loss of fuel pressure after a extended period of time specifically in the S2000 stock basket with big intank fuel pumps.

So... you add close to 80% fuel flow to the system the first thing you do is get a lot of fuel flowing in a circle and anytime you compress something you make heat. The hanger/fuel pump module/pump basket whatever you want to label that houses the pump gets the fuel returned back into it. This small volume vessel was designed to deal with the factory fuel volume. So when you induce a 340lph pump into the system it's very easy to overheat the fuel in the pump basket, once you do this the pump is in a state of cavitation and since it's a fuel pump and not a vapor pump now we are in trouble.

You can help combat this with increasing the volume of the basket and slowing the pump down to lessen volume when your just driving around. What I've done in the past is drill some holes in the basket to promote fuel being induced from the rest of the tank and letting the fuel that's been bypassed by the regulator out into the tank. A pump speed controller can be used to lessen fuel flow when you're just driving around.

Another thing to consider is tank vent. Adding fuel flow also can overwhelm the vent in the sense that you can't get enough air back in the tank in exchange for the fuel that was pumped out. Also keep in mind, there is a lot of work that goes into fuel heating as the more fuel vapor you create. The CARB/CAFE standards do their best to get the manufactures to conform to the rules. This is why the returnless fuel system was born, there isn't fuel flowing in a circle heating up... There is only enough fuel headed to the injector to meet the fueling requirements. Your car from the factory has a charcoal canister and a canister surge solenoid to re induce the vapor into the intake tract.

Jay Meagher

*edit* I have not heard about this issue specifically with the FP340 pump but since the topic came up this was the best place to post this.

Originally Posted by james0933

Just thought I'd post my Fb 340lph pump has lowered my AFR 0.5 -1 after vtec... Which is what I was looking for. This was with no adjustment and my comptech FPR Maxed out.

This was a worthwhile purchase that gave me extra room for adjustment on my kit

Originally Posted by EOE

Hmm, okay where do I purchase this fuel pump? Need it! lol


EDIT:
Never mind found it....
http://fullblownmoto...fb340-fuel-pump

answered my own question too by looking at their site...