thunderkitt3n

I was just curious how the N/A guys are shutting off their second fuel pump when the demand for fuel isn't there. are you running a window switch or do you just run both pumps all the time and deal with the extra electrical load on the system and the added heat being put into the fuel from recirculating a large percentage of unused fuel when cruising.

I'm asking this in relation to stock fuel lined 98 camaro i want to run dual pumps on for my e85 408.

thanks in advance.

JoeNova

I run my duals constantly.

JoeNova

You can run a single Walbro 485 pump for E85. They're good to ~650 wheel through an auto. I don't see the need for dual pumps on an N/A setup unless its running methanol.

thunderkitt3n

i was thinking the dual route as a redundancy in case one failed on me at some point i wouldn't be stranded and by only running one 255 lph i would eliminate some heat buildup in the fuel. if I ran a big single wouldn't i have the same issue with over flowing what my stock regulator can handle? i have read alot of guys running dual pumps on stock lines but no one ever mentions how long that setup lasts, like do the pumps only last a few thousand miles or are they lasting 20k miles before running into issues. If a big single or even small duals will run reliably on stock fuel lines then i'm all for running them full time. i really don't hear to many people having problems with vapor locked fuel lines or any other fuel heat issues.

JoeNova

The big Walbro is an OEM pump, so it shouldn't be an less reliable than a 255.

stevieturbo

20k ?

I'd be disgusted if a pump couldnt last 100k.

thunderkitt3n

I live in MN and only drive it on nice summer days and at the track, it would take me 5 years to put 20k on it. i just don't want to put a pump in that wont last very long.

i talked to Carl at CJ tunes and he said a 450 would be fine for my 550whp engine build. any other recommendations? the 450 really only flows like 380 at my pressure and voltage. I'm sure that dual 340's flow alot more then that.but i don't want to run a switch for pumps unless i don't have to, but if a single pump will work i'll run that.

JoeNova

There are a few guys here making 650whp on boost with E85 and that pump.
I'm not sure if you're underestimating the pump or overestimating your setup.

thunderkitt3n

no i've just never really looking into the 450 pump before, i always thought running that much fuel all the time would hurt the pump. thats why i was asking if people are running dual pump set ups all the time or if they are running them to a window switch. But i'll give it a shot, i'll order a 450 and see how well it works. If people are making 650 on e85 that should be fine for me, at least until i start spraying next year.

thanks for the advise.

ss454327

iTrader: (10)

The pump doesn't know if the engine is getting the fuel or it is running back into the tank.

thunderkitt3n

true, i was thinking about how the factory regulator wasn't designed to relieve the added fuel volume and would increase the backpressure on the pump. at WOT i'm sure i'd be fine, but at idle i'm sure all the backpressure is hard on the pump. i'm sure plenty of people do it though and don't have any problems with it.

kingtal0n

iTrader: (1)

No, why on earth would I run two pumps at the same time when I only need to run 1? That is what switches are for?

Part of keeping the engine happy is keeping the fuel cool. You run enough fuel in the tank to keep the temp stable and only run the minimum pump output (turn down voltage if the pump can handle it) to maintain normal driving.