Thats nonsense. Seriously. The stocker is about 190lph and starts loosing pressure when you get past the 1/4 tank mark with nothing more than simple boltons and namely and MBC. Anyone that thinks this little stock pump can handle 500whp is sorely mistaken.....or running lean....hehe

 

ok now i am confused...

Do we need to change the stock fuel pump when we flash an Evo IX with just an intake or not?

I was hoping to get a re-flash probably late Sept or very early Oct but now if i need to do more on the car i am not sure...

A simple and stright question needs a simple and straight answer: EVO IX w/ intake to be reflashed for 93 octane. Does it need a Walbro or not?

 

Take it for what its worth, but I had a reflash on my IX stock everything else for half a year and no issues whatsoever. When I added the rest of the mods in my sig, I started running a bit lean and upgraded to a Walbro and cured my issue. I think its only needed when you start running higher boost.

 

You can get by with the stock IX pump, but for under a hundred bucks, you might as well go for the 255lph HP and sell yours to a DSMr as an upgrade.

Yes the IX is higher flow than the VIII.

No your base FP does not raise or else you would see it in the short term fuel trims as the ECU would try to remove the excess fueling. THIS DOES NOT HAPPEN.

 

The issue with this family of pumps is not the rated flow capacity

It is the ability of the pump to maintain the rated flow capacity at various line PSI levels

As we modify the boost level we are requiring the pumps to flow the same or more fuel at a higher pressure

The main culprit is the increase in boost pressure means that the pump must work harder and harder to mainatin the flow rate

 

What does fuel tank level have to do with fuel pressure and pump overheating?

 

A full tank creates more preasure thanks to gravity and the weight of the fuel.... makes it easier on the pump. On a low tank the pump is doing all the work.

 

Gravity would provide only about 0.5 psi of fuel pressure if the gas tank were 2 ft tall and full of gas, so the most that gravity can help out when just driving along is about 0.5 psi. That doesn't seem like much compared to the ~40 psi of pressure that the pump provides.

 

+2 ?

 

The gas around the pump also cools it off.

 

Its not extra pressure from the weight of the fuel, so maybe this is why its bad to drive around on an empty tank.

 

The gas helps cool the pump

 

Wow That's a real stretch. Where did you come up with this?

It's simple, the fuel cools the pump.

 

Bueller......bueller..............


ahh **** it i'l go to ams

 

What about for someone without a MBC but with a flash...Shouldnt have to worry about a fuel pump righta?