I have been doing some research and so far its 50/50 opinion on what i have found if a double pump is needed. so wanted to get some opinions with the mods i have if this is gonna be necessary? Mods: fp green, gsc s2 cams springs etc.., walbro 255, all bolt ons and exhaust, fuel lab fpr, fic blue max 1450cc injectors, ams fuel rail. wanna try and run around 26 boost. So what do you guys think? so far my conclusion is if i wanna run 26psi on e85 with my green i need to go with a double pump setup. but would be ok at 21psi. Any info on this would help alot thanks!

 

You dont need a double pumper for it. It doesnt hurt though. But you can successfully run ethanol with a walbro and gain great power. I know alot of people running E85 on 28psi with their single walbro 255.

 

I'm also curious about this since I'm going from a stock turbo running e85 to an FP Red, and don;t know if I'm gonna need that extra pump

 

Cool thanks im lookin forward to the gains

 

if your going over 550whp THEN YOU NEED A DOUBLE PUMPER if your not then you can run off a single walbro but you will be pushing it.

 

Try running it on one and if you go lean then go with the double pumper. Just slowly raise your boost starting at like 20psi and watch your A/F ratios. I ran out of fuel around 22psi on 1150s with a 35r. Your larger injectors and slightly smaller turbo should help, but you might just overrun your fuel pump.

Oh and 22psi on my car was nowhere near 550whp. That is about what I make now with 33psi on a double pumper and 1150s. I would say 22psi for me is more like 420whp or so. I did have smaller injectors though.

 

when i was on my 50 trim, 1200cc injectors, E85, SINGLE walbro, 31 psi @ 489hp i was hitting about 96-97% injector duty cycle.

that should give you a little weight on your decision

 

31psi on single wally here

 

you could go with one of those new pumps MAP is releasing. Its a single drop in that will out perform a modded walbro.

 

No, just no...

 

For the Red and Green guys who posted above asking if the DBL Pumper is needed. It is not needed.

 

So you're saying trying to run 30-32 psi on the red with 1200's and a single walbro running e85 would be sufficient?

 

Yup. Duty cycle will pretty much be at 100 percent. but it will be sufficient enough to run, and make decent gains. Using a double pumper will not hurt the car, but if he absolutely HAS to have it now, then he can run a SINGLE pump.

 

Thanks for that response. Is running at 100% duty cycle bad for the car in any way?

 

no more power to be made on your car so if you do mods your screwing yourself lol get a double pumper and quit taking the cheap way out