which is stock...

 

I get that on the low voltage, low load output direction from the ecu. Wouldn't it be easier just to upgrade your FPR to an adjustable unit and then fix the voltage at battery level than risk damage to the pump by forcing a big pump to operate slower and at a lower voltage than designed?

 

i am running an AFPR... but
a) I dont want to run less than 30psi base, because I think the spray pattern suffer
b) My return system doesn't allow for less than 35psi with the E85 400 pump

Why will the pump be damaged at lower voltage? Is that something common for electric motors?

 

Why aren't you running 43psi +/-?

 

Fic2150

 

I would still target stock base pressure, 40psi at the lowest and then trim the injectors using scaling and dead time

 

the trims are fine.

my main problem is that the 1.15 odd IPW that the injectors need to run 14.7 is a bit too low for the injectors to run at reliably..

hence when I have lowered the fuel pressure to 30/35, so that I need a higher ipw.

but if I can also reduce the flow with the pump (by lowering the voltage) then that might help as well)

 

been there done that with the low voltage resistor on my w400. with a 0.55 ohm resistor, the pump would run at engine idle where the fuel rail pressure was about 37 psi, but as soon as rail pressure passed about 40 psi, the pump would stall. with the stock resistor, i found that the pump would stall if i raised the full voltage xover to more than the stock value of 100 load. i actually ended up going to a higher than stock resistor so that i could run higher than stock xover load because pressure across the injectors would jump about 10 psi above the 43 psi target when triggering at 100 load and would stay high up to about 150 load. i'm getting slight overrun at idle, but nothing like what you mention.

 

Its a very interesting thread at the least and one I'm paying attention to. I'll go brainstorm for a bit. haha

 

thanks mrfred,

I dont think my pump stalls with the stock resistor even upto 55psi... my load xover is 140, and when passing that I dont seem to notice the AFR going rich or anything like that (to indicate a massive increase in pressure)

so did you run 2 resistors or just the stock one?

 

ok, Sounds like the W465 is substantially different than the W400. I ran a single resistor in place of the stock one. I bought a very robust 100 W resistor, and if it fails, no big deal... Its either going to short out producing full voltage mode, or its going to going to become an open circuit. Either way, it only affects the low voltage pump circuit and not the full voltage circuit.

 

well ive had both Walbro 400 pumps no (regular and E85).

To be honest I havn't tried driving the E85 one above 45psi, but the regular one operated fine between 30 and 55...

 

When you were running the w400, did you try higher-than-stock values for the xover load when running stock or higher-than-stock base pressure?

 

i had higher than stock xover.. but i had no need for higher than stock base pressure...

 

my normal Walbro400 has had no issues and has ONLY seen e85. I got it when they were very first released. Base pressure 40 and ramps up to 85-82 under WOT, no issues ever. It is ran parallel w/ a 044, both maxed currently. LOL. Currently looking into a KB BAP