I'm running out of gas. The fuel pressure starts dropping at about 4000 rpm, down to 42 psi by 5000 on a WOT run, and the AFR starts leaning out at 4000. Full tank. I installed a new stock pump/bucket assy. last summer. With my new engine, I put in a new filter, and a brand new MagnaFuel 4301 inline. I replaced another 4301, it somehow got noisy during the motor job.
Does anybody have a similar set-up? I can't believe that the stock pump or bucket is acting as a restriction.

 

Its a pressure problem. Put a Bosch 044 pump inline off your main line and you should be fine.

Rick

 

Are you saying the MagnaFuel is a P.O.S.?

 

no, just sounds like its not working for you.

Have you tried just a solid intank 420 pump yet? Thats what I run.

Rick

 

Also, couple things could be happening.

What gauge are you using for fuel pressure?

At what MAF Hrtz value are you dropping AFR?

rick

 

I'm using a Johnson Controls P399AAC-1C. It has the same characteristics as the Autometer, it was just cheaper for me.
I'm running 2-bar SD, pressure starts dropping at 150 kPa.

 

walbro 255 and ride!!

 

What is a 420 pump?

 

Are there known issues with the MagnaFuel inline pump that claims to support 1000 HP that are unknown to me?

 

Bosch