hi guys, Recently I did my feed fuel line 3/8 and rewire the pump walbro 255lph.

The old command flow Regulator can't control the extra flow, so I switched to a AEM.

I put the AEM at the same psi as the old reg. 52psi, but the WOT AFR's seems a tad different now (from 11.2 before to 11.7 now)

Do I did something wrong setting the AEM? do I need to retune the car? The car is running more lean with more fuel flow. Why?

thanks in advance.

 

Are you sure you were running 52 PSI before? 11.7 is still safe from what I have heard. You can turn up the fuel pressure to get down to 11.2, not sure if that is the right way to go about it though.

 

yes, sure it was at 52psi.

Na man, I prefer to clean the tune, rather than rise the pressure.
But this time I have to do it in the street, I'm broke to rent the Dyno.

I'm asking because the different orifices and settings in the AEM.

thanks.

 

If its the same psi then its fine. Although I would prefer to see the pressure at boost vs at idle (perhaps the rising rate is exactly the same).

However 0.5 AFR is within the margin of error, especially considering weather changes. Just clean up the fuel map or adjust the fuel trims.

 

This morning I note that the press is at 50psi and I think maybe I left the adjuster nut not properly tight but after set it again to 52psi and a little run around the block the thing went to between 50-52psi.

I think is the gauge, I'm going to change it.

 

update, Today I remove the lid in the floor access to the pump assy. and start the car the pump whine but at the same time make a sucking, slurping sound.

Like it was starved from fuel but the car is half tank. So I think maybe the pump filter fall off, but after remove the assy. all was fine.

The pressure still rock solid at 52psi now.

This isn't my first walbro but the first rewire so maybe I'm making a storm in a glass of water.