Dual intank fuel pumps

[BluemeanieTSi]

i started trying to figure out how to put dual pumps in the stock housing but that wasn't happening without major hacking. since it was my only housing i had i started looking for alternatives so i decided to build my own.

the housing cost me about 10 bux and 2 days to make, i still need to wire it.

here's what i started with but this ended up not working well due to return line placement.

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the housing isn't all that thick it was the thickest metal i could find at the local tractor supply company. i just cut a circle to match the upper piece and welded a support rod to it, then welded the inner ring piece for the gasket, test fit to make sure it sealed ok then started on the feed lines. they are 3/8th brake line i bought 3/8th brake unions and ordered 3/8th flare to 6 an fittings from summit. the housing cost me around 10 bux and the fittings cost around 15 total for that part.

(ignore the twisted screens the pumps weren't secured yet for this pic)

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after about a days work (i'm not much for planning things out) i realized i had no room for wiring or a return line. soooooo i started over

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the two 45 degree 6an hose ends clear the back seat with no modification following the factory feed lines. the "y" block is a BG (barry grant) fuel block i got from jegs for around 30 bux and it is 3/8th NPT, it comes with a pressure tap source that needs to be plugged (i see no need to put a gauge back there) the lines are 6 an then 3/8 to 6an 45 degree fittings for inlefts with a 3/8th to 8 an and 8 an line from then on.

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i kept the float for street car use, and i kept the gauge light crap just so i didnt' have to cut it apart. the return line is 3/8th and the vent is 1/4 brake line, i'll be using the factory feed hard line as a larger return line so i dont' have to run another line under tha car i'll use the existing one which i think is 5/16ths

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everything is soldered with plumbing solder and leak tested. here's a good shot of the flare to an fittings from summit.

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here's what i have so far, all the lines (not cut to length) and the filter i will be using (caution this filter is over a foot long) everything is 8an from the y block up including the rail. i will be using a magnafuel fuel pressure regulator as i was not impressed with the aeromotive one i had been using in the past.

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questions, comments, personal experiences......for reference i'm planning on an fp3065 for the setup at the moment.

 

[BluemeanieTSi]

there's mine and i think i made 3 1g ones (one didt'n make it in a wreck) we made after killing them trying to put pumps in. i'm too much a stickler for quality to sell them to other people.

 

[Tevenor]

Hell, I would be in the market just for a 2G SS replacement housing for my single Walbro with all 6AN fittings.

 

[BluemeanieTSi]

mine isn't stainless..and the pumps are held right now by a ziptie rather than the rubber piece (can't fit that with duals) i wouldnt be comfortable selling that to someone, plus i cut the metal with a cutting wheel...kinda sux

 

[GRNDSM]

Why not use SST radiator clamp to hold the pumps?

 

[BluemeanieTSi]

Why not use SST radiator clamp to hold the pumps?

what i wanted to do was support both pumps from the bottom like the factory does...but i'll probably use the clamp then

 

[Vegas Smith]

thanks for all the support, figured i'd get some "what the hell u need that for" comments but to each his own

I was not tyring to be a jerk. i had just never heard of anyone doing this on a street car and was just wondering why.

As for the others claiming we have no idea how to get low 11's, low 10's....I have a buddy with a 550hp talon, and one with close to 600hp and neither have duel fuel pumps. go figure.

Nice work though.

 

[BluemeanieTSi]

i was never saying it couldn't be done....i just was saying that at that point you start running the fence...i'd rather have too much available in that situation than not enough

 

[hostile]

I was not tyring to be a jerk. i had just never heard of anyone doing this on a street car and was just wondering why.

As for the others claiming we have no idea how to get low 11's, low 10's....I have a buddy with a 550hp talon, and one with close to 600hp and neither have duel fuel pumps. go figure.

Nice work though.

550 is right on the fence, just like he said.

There are ways to make a smaller pump work, like taking a huge set of fuel injectors and dialing down the base fuel pressure. If you keep the total pressure down the walbro will still keep up with the fuel FLOW demand.

That is why the 255 will support upwards of 600hp on turbo mustangs and buicks.

Neat install, I have a buddy running two 255's in his mustang. He wired the second one in on a hobbs switch so it wouldnt be running constant.

You could also use your engine managment to control the second fuel pump if you had something like the EMS or dsmlink.

 

[BluemeanieTSi]

550 is right on the fence, just like he said.

There are ways to make a smaller pump work, like taking a huge set of fuel injectors and dialing down the base fuel pressure. If you keep the total pressure down the walbro will still keep up with the fuel FLOW demand.

That is why the 255 will support upwards of 600hp on turbo mustangs and buicks.

Neat install, I have a buddy running two 255's in his mustang. He wired the second one in on a hobbs switch so it wouldnt be running constant.

You could also use your engine managment to control the second fuel pump if you had something like the EMS or dsmlink.

why make it complicated, the fpr i'm using supports "up to 2k hp" so i'm pretty sure i won't overrun it...it's 1:1 so i'm keeping it simple

 

[lambertvr4]

Very nice setup. I will do something very similar in my Galant with two Supra pumps. I would suggest installing one way valves between the pumps and the Y (collector). This way if one fails the other will not pump back through the other and starve the engine for fuel. I've seen that happen on a Lightning which has dual intank pumps. The truck would barely run and the dealership replaced both pumps because the "good" pump was overworked and was on its way out too.

I've also thought of connecting a Hobbs switch to control when to turn on the second pump. This could be tricky to ensure that the fuel pressure doesn't spike when the fuel pump kicks on. That may not be a bad thing though when the boost is ramping up. I may try it just to see.

I personally have tuned a Civic to 580wHP with a 255 Walbro on a DynoJet. That's at 46psi base fuel pressure and 26psi of boost. That's at 9500RPM. I'd be surprised if the 4G63 engine would make as much with that pump, but it won't be that much less. Honda's are very efficient at making power. Not trying to stir the pot. Just trying to add personal experience.

 

[BluemeanieTSi]

Very nice setup. I will do something very similar in my Galant with two Supra pumps. I would suggest installing one way valves between the pumps and the Y (collector). This way if one fails the other will not pump back through the other and starve the engine for fuel. I've seen that happen on a Lightning which has dual intank pumps. The truck would barely run and the dealership replaced both pumps because the "good" pump was overworked and was on its way out too.

I've also thought of connecting a Hobbs switch to control when to turn on the second pump. This could be tricky to ensure that the fuel pressure doesn't spike when the fuel pump kicks on. That may not be a bad thing though when the boost is ramping up. I may try it just to see.

I personally have tuned a Civic to 580wHP with a 255 Walbro on a DynoJet. That's at 46psi base fuel pressure and 26psi of boost. That's at 9500RPM. I'd be surprised if the 4G63 engine would make as much with that pump, but it won't be that much less. Honda's are very efficient at making power. Not trying to stir the pot. Just trying to add personal experience.

i was under the impression the pumps themeselves cannot flow backwards when shut off

 

[Car Cannibal]

Nice job, would not be surprised if some shop fabs up pieces like this in the future.

Good luck with your project, sounds like a fun ride.

 

[Chargedawd]

That is some really nice work. My only question is that if you are maiking your target goal of 500 whp you want to have the cushion of extra fuel you dont have any way to tell if 1 of the pumps dies. That could lead to some pretty serious engine failure.

You could always put in 1 way valves before your Y junction and a pressure sensor on each line so you could be certain both pumps are running.

But like I said, good work on the fab

 

[BluemeanieTSi]

That is some really nice work. My only question is that if you are maiking your target goal of 500 whp you want to have the cushion of extra fuel you dont have any way to tell if 1 of the pumps dies. That could lead to some pretty serious engine failure.

You could always put in 1 way valves before your Y junction and a pressure sensor on each line so you could be certain both pumps are running.

But like I said, good work on the fab

fuel pressure gauge inside the car (electronic) should tell me if one pump fails

 

[GRNDSM]

Very nice setup. I will do something very similar in my Galant with two Supra pumps. I would suggest installing one way valves between the pumps and the Y (collector). This way if one fails the other will not pump back through the other and starve the engine for fuel. I've seen that happen on a Lightning which has dual intank pumps. The truck would barely run and the dealership replaced both pumps because the "good" pump was overworked and was on its way out too.

A fuel pump also serves as “one way valve”, that is how our cars retain fuel pressure when shut off. Some aftermarket FPR and pumps are more prone to leaking and loosing that fuel pressure over 1-5 mins, but that should not be enough to cause low fuel pressure.

I suppose that this is possible for a fuel pump fail in a way that causes it stop being one way valve, but it seems pretty unlikely.

I've also thought of connecting a Hobbs switch to control when to turn on the second pump. This could be tricky to ensure that the fuel pressure doesn't spike when the fuel pump kicks on. That may not be a bad thing though when the boost is ramping up. I may try it just to see.

You could just control the second pump through AEM, DSM link or some other standalone .

 

[BluemeanieTSi]

A fuel pump also serves as “one way valve”, that is how our cars retain fuel pressure when shut off. Some aftermarket FPR and pumps are more prone to leaking and loosing that fuel pressure over 1-5 mins, but that should not be enough to cause low fuel pressure

good, then my information was correct

 

[Mike 99GSX]

With both pumps running at the same time, how will you be able dial back enough fuel pressure with that regulator and such a small return fuel line? Maybe I'm missing something obvious but isn't the base pressure going to be like 70PSI even with the ADJ FPR all the way at its end of adjustment?

 

[BluemeanieTSi]

With both pumps running at the same time, how will you be able dial back enough fuel pressure with that regulator and such a small return fuel line? Maybe I'm missing something obvious but isn't the base pressure going to be like 70PSI even with the ADJ FPR all the way at its end of adjustment?

what small return line?

 

[Mike 99GSX]

what small return line?

Before I switched to a fuel cell/Aeromotive pump, my friend and I briefly experimented with twin 255s when the car ran out of fuel around 550whp. It was a -10feed and -8 return. My friend drilled out the return orifice on the Aeromotive regulator as well trying to lower the base pressure but it still was over 70 PSI with both pumps running at idle.

 

[BluemeanieTSi]

i'm not using an aeromotive regulator and i am using the same size return as the feed. on a side note about aeromotive, one rewired pump was overflowing my aeromotive regulator i couldnt get below 42psi at idle, maybe it was a regulator problem

 

[Mike 99GSX]

i'm not using an aeromotive regulator and i am using the same size return as the feed. on a side note about aeromotive, one rewired pump was overflowing my aeromotive regulator i couldnt get below 42psi at idle, maybe it was a regulator problem

It certainly could be a regulator issue that was why I was asking. Have you hooked this up yet and been able to successfully dial back the base FP to the 40-50PSI range with that regulator?

 

[BluemeanieTSi]

It certainly could be a regulator issue that was why I was asking. Have you hooked this up yet and been able to successfully dial back the base FP to the 40-50PSI range with that regulator?

no i odn't have the motor from the machine shop, i'm building the fuel system while i wait, the rail should be here this week along with the regulator but it's hard to test without the motor in the car.

 

[Mike 99GSX]

no i odn't have the motor from the machine shop, i'm building the fuel system while i wait, the rail should be here this week along with the regulator but it's hard to test without the motor in the car.

I'll be interested to see if this works out or not. I am still using the same Aeromtive regulator with the new external Aeromotive fuel pump and I can dial the FP all the way down to under 35PSI. I still don't really understand how I could get the twin Walbros even close to that by comparison.

 

[BluemeanieTSi]

I'll be interested to see if this works out or not. I am still using the same Aeromtive regulator with the new external Aeromotive fuel pump and I can dial the FP all the way down to under 35PSI. I still don't really understand how I could get the twin Walbros even close to that by comparison.

i don't like external pumps for a couple reasons but i'll let oyu know how it works

 

[lambertvr4]

I don't know if the pumps will backfeed or not. Considerring the arguement about sustained fuel pressure after key off, I'm sure it wouldn't be bad. However, that is at base pressure, not 80psi of fuel pressure under boost (assume pump failed). It may also depend on how the pump fails I'm sure.

One way valves are cheap. If Ford replaces both pumps when one fails on a stock vehicle, then I'm inclined to take precautions. It's not that much more money. I don't have too much experience designing fuel systems or even experience with this setup. Sounds reasonable though and my post was only a suggestion anyway. Take it or leave it.