as far as I know an after market pump with increases GPH should work on a stock setup, since the fuel system likely has a pressure sensor to tell the ECU what's going on.

...at least that's my theory.

 

I wonder if the ECU has any such circuit. But my thought is that the fuel pressure regulator would take care of any problem that a high gph pump might cause.

 

no, the Pressure regulator that is mounted on the rail equalize the pressure for the fuel injectors to get equal amount of pressure. The Fuel sensor on the pump probably have to do with the vapor

 

i'm looking at future proofing with a Walbro 255 GPH or an AEM 320 GPH. One gets to wondering if that could richen up the fuel mixture with a bigger pump and or possible higher pressure to the regulator or injectors?

Now bigger injectors i think for sure richen things up until reprogramed?

 

What year car? I believe the 02-03 pressure is controlled by the ECU adjusting voltage without a pressure regulator. The pressure stays a consistent 51 PSI directly from the pump no matter what. I'm not sure how that would work with a larger pump.

Increasing the fuel pressure, however you do it, will make it run rich.

Larger injectors without a tune will certainly make it run very rich.

Why do you want to increase the fuel pressure? Are you planning a large turbo setup?

 

00-01, everyone acts like the 00-01 are wired completely different with different ECUs.

mostly future proofing if i do a stroker 3.0 or stroker 3.5 and or forced induction. also the pump is showing signs of wear and hard starting. why not high quality Walbro or AEM.

 

There are some differences between the two. The ECU controls more on the 5.5 gen. I'm pretty sure the 00-01 does have a pressure regulator while I know the 02+ doesn't.

I don't see why you shouldn't do it, especially since you do have the regulator. I just don't think you're going to outflow the stock pump unless you run a big turbo setup. See what the guys in the FI forum are doing for fuel.

FWIW, I thought a hard start in my 00 was the pump so I replaced it at 300,000 miles but it was fine. It's pretty rare to hear about fuel pumps failing on these cars. I'd confirm the pump is bad before spending the money on either pump.

 

I ordered a Kemso GSS340. Everywhere I've ready says they perform better than the Walbro and provide more fuel. AND they are like half the price. I haven't installed it yet, because I'm waiting on my turbo manifold