most pumps internally bypass before 85 psi. nearly everyone sets their base fuel pressure at 43 psi or so. add 30 psi boost and the rail pressure is 73 psi. with stock lines there is a lot of pressure drop from all the fluid friction and to get 73 psi at the rail, the pumps are most likely bypassing and you have to compensate by adding idc at the fuel map. mrfred did some great tests to show the pressure drop, it was pretty ugly with the stock lines.

personally, i think if you plan on running over 30 psi boost and/or 550 whp on e85, run a -6 feed and use the stock feed line as a return.

 

Cheers mate great information.

What fuel line to most people run and where do they run it?

Just under the car like stock or internal or down the chassis rail?

 

I agree, but the downside to the E85 walbro pumps is that you have to get a new FPR, mod the siphon, and change the high voltage crossover for them to work as intended... Not saying that is a bad thing, but we all know how everyone wants to go fast on the cheap around here...

 

yeah I see your point.

 

i do not think you have to do anything in upgrading wire or the siphon. it will work without that. at least that is what some have said.

 

Correct the pump will "work" without the rewire, however you loose a lot of the pumps capability... if it is rewired, it needs to have the siphon drilled and an adjustable FPR or you may be able to sneak past it with adjusting the high voltage crossover point, but I would recommend an AFPR...

 

the squash setup has its own return venturi, nothing to drill. and the harness is all good. only thing is the fpr. he will have a solution though, a pwm controller that you can even use to run a returnless setup if you want.

 

I remember the walbro guy saying their ethanol pumps didn't like pwm controllers, rather voltage controllers to limit pump flow. He asked me how I triggered the second pump.

 

Bump on pricing with twin E85 pumps

 

Bump on any prices please

 

so excited for this to come out!! need prices!!!

 

No mods to the siphon with our unit under any circumstances. The stock wiring isn't up to the task of powering these pumps. You might get away with powering one with the stock wiring but it will have pretty good voltage drop due the current the pumps can pull.

Andy

 

Okay, with your unit and siphon with the primary Walbro E85 pump rewired will it over run the stock FPR on an evo with stock lines?

 

The siphon doesn't enter into it...

As far as overrunning the stock FPR with one of those pumps, it's going to be close. I haven't actually tested it against the stock FPR yet. The stock return line is really small, but it should handle the flow of one pump at full tilt, barely.

Andy

 

Pricing has been posted: https://www.evolutionm.net/forums/ev...l#post10541335