rx_treme

iTrader: (9)

It's hard to say whether your external walbro with an intank will suffice. All of the flow data for walbros are based upon suction feed. When you pressurize the inlet it will increase the flow.
Lots of us run dual externals. I run dual external bosch 044's with an in tank walbro feeding them

lavoy

iTrader: (2)

i run twin walboros, both external off my sumped tank, no issues, unless you count the fact one is starting to get very loud, i called walboro and they claim getting loud is not a sign of anything wrong, but i have to wonder why it was quiet for 4-5k miles and then got loud.

Camaro Ken

Ok good to know. N walbros probably bs'ing u man.

Camaro Ken

Oh and one more question. I'm using a c5 filter as my regulator will that be ok or do ineed to go with an fpr.

ls6427blown

my friend is running two for about a year now no problems

KRAZY K 2000 TA

iTrader: (5)

i am running two but i have a return style system with a magnafuel regulator after the rails. before with the corvette filter it would have 60 psi with one pump and 70 psi with both pumps.

Packy

iTrader: (11)

What kind of mods to the bucket are you guys doing to run two Walbro pumps in there?

blackmagicturbo

iTrader: (2)

I think the main reason for death on a fuel pump is fuel line restriction, I run -8 line with mine just because it didnt seem right to run through such a small line,, plus it probably makes the fuel cooler.. im running 4x 255 inlines on my camaro to -10 line .. lol

Lonnies Performance

iTrader: (16)

Line size is not the problem, but the power required (heat generated) to run 2 pumps, plus the heat pulled from the rails/engine compartment & returned to the tank is the problem.

Excess pump capacity when not needed is just adding to the heat load on the system.

Packy

iTrader: (11)

I am having that issue a little bit. I took my bucket out the other day and noticed that there was a bit of heat coming from the tank. I didn't think that a return system would cause that much heat but my car runs at about 200 degrees when cruising under load and the ambient temp is above 90 degrees here FL. This was after driving for about an hour or so.

Lonnie any bad side effects from the warmer fuel? Obviously higher IAT's but is there a fix like a fuel/trans cooler sort of thing.

Lonnies Performance

iTrader: (16)

The hot fuel is what causes the pumps to cavitate. This is hard on the pump & can shorten life. Also in severe cases they can vaporlock & stop pumping fuel leaving you stranded until the fuel cools.

JoshuaGrooms83

iTrader: (2)

i already have a return system on my car for my car, but ive noticed that the line going back gets pretty hot! im wondering if i should get a fuel cooler.

NightmareTA

iTrader: (20)

I run twin in tank walbros all the time. I have -8 line from the tank to the rail, with a "T" in the line and back into the factory LS1 style in-tank reg. As other's have said, my pressure is a bit high, and usually stays around 70 PSI. I plan to remedy this by removing the in-tank reg and putting an aftermarket return-less style up by the rail. That way I'll have a full -8 return line to dump all the excess fuel back into the tank. Should be MUCH less of a restriction than the crap factory reg.

JoshuaGrooms83

iTrader: (2)

would a 3/8 hardline be ok for return duty? (= 6an hose +/-)

i have my aeromotive FPR hooked to the fuel rail and then returned back to the tank via its own dedicated return line. i am thinking though to reduce some of the heat transfer to the hard line to put a short an hose between the FPR and the hardline.

not planning on that much hp, id like to be about 650ish with the extra pump. i already have a racetronics pump, and might get another, but im also holding out to see if racetronix comes out soon with a larger single pump in the 400 range. they have a pump but waiting to see if they make it drop in compatible.