I'm Confused About The Surge Tank Setup

[SargeRX8]

Hey all,

Well Ive been reading about setting up a surge tank but am a little confused. I'm still going to gather parts either from for sale here or make do with what my brother has spare.

Anyway first thing is first. Ive read other topics here but I need pictures to see how everything goes. The fuel cap in my r33 gtst has 3 hoses... Out, in and I have no idea what the third one is.

I need these clarified before I go further. A picture I found on this forum showed fuel being fed to the fuel pump by one line then an overflow line going back into the fuel tank. Does the overflow line return back into the old return line from the engine and then the return line from the engine goes into the surge tank? This brings me to my next point. Would this cause the cycle of fuel to be the same fuel going to the engine and coming from the engine to sit in the surge tank? How does it get circulated quick enough? Is there a way to return the fuel from the engine back to the fuel tank to encourage the flow of petrol so it doesn't heat up too much or is it fine the way it is.

My setup would and most likely be as the diagram below consisting of the following pumps, bosch 040 pickup and a bosch 044 feed. Ive read about overpressurising the surge tank but some chap at boost cruising said he has been running a 040 pickup and twin 044 pushers for a while now and had no issues, he said as long you have an overflow line you don't need to worry about overpressurising.

Now my CAD professional level diagram:

Is it going to sound like someone is tanking a piss in my boot? I need some input here. Also, is it fine just to use EFI hose or do I need to use that braided shit?

If you could post pictures of your setups, that would be awesome.

This is going into a gtst currently on 330hp with potential for 380 - 410hp on fuel pump.

Cheers all

[Piggaz]

Im running a Nismo feed (aftermarket intake pump) into a 5 litre surge tank with twin 044's feeding the engine. Dash 6's all round, however it would be nice to have a dash 8 for the return lines. So, from the FPR it goes back to the surge tank then a overflow line back to the main tank.

You dont need braided lines... Rubber hose is fine.

You can't hear the overflow dropping back into the main tank.

Are your tracking the car? If not I wouldn't bother with surge tanks with feed and lift pumps. A single Nismo will do the job without any problems.

[boostn0199]

Basically you need 4 ports on the surge tank. The bottom one goes to your 044 then that goes to hose that was previously the feed on your fuel tank.

Then your next hose on your surge tank goes into the feed side of the fuel tank so the lift pump can fill the surge. The next one up connects to the hose that used to conect to the return side of your fuel tank and now the final top hose on the surge tank goes back into the return side of fuel tank and this line is what prevents any pressurise issuses since if the surge overflows it can just go back to your tank.

[boostn0199]

And that third little hose is the breather dont worry about that.

[KiwiRS4T]

You are right . Ideally the return from the engine should not go into the surge tank (although it seems plenty do). The petrol can get very hot and some people actually incorporate a fuel cooler into the return line.

[JonnoHR31]

to have the engine return go back into the main tank you'd need your lift pump to flow more than your main pump at all times, which would get the surge tank even hotter than running a conventional setup.

OP: you dont need a 040 as a lift pump, use a stock pump, you dont even need to wire it up for more voltage.

personally i like to have surge tanks set up like this:

top port: overflow to main tank

second port: return from engine

third port: feed from tank

bottom port: feed for main pump.

[R31Nismoid]

What's the use of the car?

Unless you external mount or spring for expensive lines that don't weep, you'll have to live with constant smell of fuel

[75coupe]

why dont you just go without a surge tank and keep the tank over half full when on track...

then you dont need a surge tank, aint that right??

unless your pullin huge G's on the street with less than a 1/4 of a tank...

my understanding with a surge tank is its just so the pick never comes out of the fuel, hence hard cornering on low tank level...

is this a street car or a track car..?

[ahh 33 s2]

On the topic of surge tanks, has any one got a wiring diagram for wiring up the external pumps, or is it just an addition to the standard pump wiring? I've read the diys on re wiring the intank,

[SargeRX8]

On the topic of surge tanks, has any one got a wiring diagram for wiring up the external pumps, or is it just an addition to the standard pump wiring? I've read the diys on re wiring the intank,

Direct feed from battery to a relay, use the existing fuel pump positive wire as your trigger wire and then feed your pumps directly off the battery. The thin wires on the standard wiring system aren't sufficient to feed 3 pumps.

Also the car is a street car. I want one just incase I do start going tracks I won't have to do it later. Also as a fail safe just to ensure I never get a gulp of air.

Edited July 2, 2011 by SargeRX8

[blue_vl_t]

to have the engine return go back into the main tank you'd need your lift pump to flow more than your main pump at all times, which would get the surge tank even hotter than running a conventional setup.

OP: you dont need a 040 as a lift pump, use a stock pump, you dont even need to wire it up for more voltage.

personally i like to have surge tanks set up like this:

top port: overflow to main tank

second port: return from engine

third port: feed from tank

bottom port: feed for main pump.

if your setup is fairly basic, just do this, works well, circulates fuel and gets a bit warmer,but its how most surge tanks are setup.

to change the setup, as said above, you would need a larger intank pump that the one drawing from your surge tank to then have your fuel rail ruturn going straight to the tank.

[KiwiRS4T]

to have the engine return go back into the main tank you'd need your lift pump to flow more than your main pump at all times, which would get the surge tank even hotter than running a conventional setup.

OP: you dont need a 040 as a lift pump, use a stock pump, you dont even need to wire it up for more voltage.

personally i like to have surge tanks set up like this:

top port: overflow to main tank

second port: return from engine

third port: feed from tank

bottom port: feed for main pump.

The lift pump is working at virtually no pressure whereas the exterior pump is working against minimum 2 - 3 bar even at idle plus a number of other flow restrictions - why would the surge tank get hot under these conditions? The heat comes from the engine (and maybe a little from being presurised) not the pump.

[wolverine]

What's the use of the car?

Unless you external mount or spring for expensive lines that don't weep, you'll have to live with constant smell of fuel

why dont you just go without a surge tank and keep the tank over half full when on track...

then you dont need a surge tank, aint that right??

unless your pullin huge G's on the street with less than a 1/4 of a tank...

my understanding with a surge tank is its just so the pick never comes out of the fuel, hence hard cornering on low tank level...

is this a street car or a track car..?

x2 to both.

Just stick a good quality high flowing pump in tank.

[Dobz]

What's the use of the car?

Unless you external mount or spring for expensive lines that don't weep, you'll have to live with constant smell of fuel

I've got a custom aluminium surge tank using brass fittings, efi hose and efi hose clamps in my boot with no fuel smell at all. The commom causes of fuel smell are pin holes in welds, hose clamps loose, not using fuel hose, roughly tapped holes for fittings and/or no fuel resistant thread sealant used.

[R31Nismoid]

Direct feed from battery to a relay, use the existing fuel pump positive wire as your trigger wire and then feed your pumps directly off the battery. The thin wires on the standard wiring system aren't sufficient to feed 3 pumps.

Also the car is a street car. I want one just incase I do start going tracks I won't have to do it later. Also as a fail safe just to ensure I never get a gulp of air.

If its not a dedicated track car then honestly you are wasting your money mate as the R33 tank is fine. Why spend $500+ on surge tank, new pump, lines/fittings and wiring for nothing?

All the 350-400rwkw CIRCUIT GTR's down here, on semi comps - use a single in-tank pump and just don't get low on a tank (my car included). It's as simple as not going under 1/4 of a tank, and correctly mouting the fuel pump.

The only way you'll get a gulp of air is if you end up with the car on it's side. And that would be the least of your worries.

[JonnoHR31]

The lift pump is working at virtually no pressure whereas the exterior pump is working against minimum 2 - 3 bar even at idle plus a number of other flow restrictions - why would the surge tank get hot under these conditions? The heat comes from the engine (and maybe a little from being presurised) not the pump.

yer but even under pressure if the cars just idling (least pressure) the 044 is still gonna be pumping over 200lph effectively straight from the surge to the main tank. so even though your lift pump isnt pumping against pressure it'd still have to flow well over 200lph. and the pumps do generate a lot of heat, which in turn heats the fuel. its just an all round bad idea to plumb it up like this, not to mention more costly for no gain.

[Piggaz]

^^

Better get on the blower to Rob from RIPS then. He might learn something

[G37Sam]

Sorry for bumping an old thread but while on the topic of surge tanks, those of you running external surge tanks and pumps, do you do any sort of thermal insulation to them to keep the exhaust heat away from them? How far away from the muffler are your surge tanks generally?

I'm thinking of running one between my mufflers but I'm worried things may get a little hot down there.

[GTSBoy]

THe convective cooling power of undercar air flowing over the surge tank would have to be about a thousand times more powerful than the radiative heat transfer from the exhaust components to the surge tank.

[G37Sam]

True that, but what happens when you're sitting idle in traffic?