fuel surge tank, how to set up?
 

hey guys.
after having a fuel tank made up we have realised after driving a fair bit now, that it needed more baffles inside, the reason for this is because when we turn to one side the car starves for fuel, you can feel and hear it,
im thinking of putting a fuel surge tank in the boot.
just wondering who has done this?
has it stopped the problem?
how do i set it up? do i need to have 2 pumps running? one from fuel tank to the surge tank then to the engine?

thanks
Daniel

Yep that's exactly right. You need a low pressure high volume fuel pump from your big fuel tank to the surge tank. Surge tank should be at least 2 litres. You need an overflow from the top of the surge tank back into the big tank. Then your regular fuel pump should feed the engine from the bottom of the surge tank. You can buy pre made ones from perfoance shops / eBay etc.

You could always try a canister filter in line right before the fuel pump, this way the pump is drawing off that filter and then the air suck through won't be such an issue. Just depends what pump your running.

Fuel surge tank
 

I made a surge tank out of an aluminum C02 welding cylinder (small) installed upright in the boot. I tried several configurations and the one that worked best with fuel injection was plumbed as follows. I used a Holley blue pump to feed a bung that I installed on the side of the tank near the top. I feed my Bosch fuel injection pump from a bung I installed near the bottom of the tank. I feed the returned fuel from the EFI regulator at the top of the tank. I also installed a 5 psi check valve at the top of the tank that routes fuel back to the main tank on the opposite side from the fuel pick up. This set up insures that the Bosch pump always has at least 5 psi of pressure feeding it and that the C02 cylinder is always full and under pressure. I have an electrical bypass on the Holley pump so that I can drain the main fuel tank by running that pump and connecting a drain hose to the C02 cylinder where the check valve is normally connected. This set up has worked perfectly under high cornering loads. I initially returned fuel from the regulator right to the tank but found that it would occasionally get air and cause a stumble because the tank could run out of fuel on a long LH sweeper, so I now return fuel directly to the C02 bottle.
My tank is baffled and I have tried duel pick ups and even a swinging pick up but this is the only set up that worked perfectly even with only a gallon or two in the tank.

Daniel, I had exactly the same issue. My tank is a fairly wide flat tank without any baffles etc.

Put in a surge tank and have never had a problem. My Surge tank is about 0.6L and I havent had any starvation problems even on the track.

The Low Pressure Pump is a Carter Lift pump and the High Pressure pump is a Bosch 044. I'd recommedn placing the Surge Tank higher thank the high Pressure EFI fuel pump as they dont suck very well.

The alternetive you could do is to put in a late model pump from say a VE commodore that has the surge tank, fuel sender and fuel pressure reg built in. You just need a deepish tank.

Below is a plumbing diagram of what I did. (there a copy in my gallery) Cheers Gregg

http://www.clubcobra.com/photopost/d...urge_Tank1.jpg

Here are some surge tanks available in Victoria:
Surge Tanks

The 850-110 is popular for EFI engines.

Or Daniel you could bite the bullet and take the tank from the car and have it opened up and properly baffled.

Finding space in the cobra for a second tank, extra pump and then having to re-wire isn't impossible but a right pain in the backside.

In fact I did the reverse and had an in-tank pump fitted into the manufacturers tank that came with the car.

This also has the advantage of keeping the pump noise to a minimum as you'll find the Bosch 044's and the like can be fairly noisy externally to the fuel tank.

Bit of a pain having to dismantle the car, and you have to go through a pretty thorough tank rinsing process over two or three cleans. This is a must to ensure there are no petrol volatiles in the tank to go bang when you start to shower it with sparks and heat.

But I would suggest the easiest fix for your issue.

Slo

like Stephen said
I would think about getting your orig tank modified,
find an efi intank pump that will fit if yours doesn't have one,
then get someone to weld in a swirl pot inside where the pump will sit
and they can even make plates that flip to let fuel in but not out
this way it might cost a touch more for fab work but u have less stuff outside the car

running 2 pumps and a surge tank adds about 6 or 8 extra hose connections which if done properly is fine but I like to make things less complicated and less chance of problems down the track

go visit some good fab shops who do this often and tell them what u want to do to the tank and se what they suggest

if you have limited room and low cars running a surge tank and 2 pumps can be a pain
as like others have said external efi pumps don't such to good as they like to push better
so if its mounted to high then u get the fuel cavitating and also starving and also the fuel pump can make rattling noises

Here's what we did to allow us to get around the NASCAR oval and stop the fuel starvation issue.....we use the low pressure high volume small collectors to pump to the main collector pickup, then to the high pressure pumps to the motor.

Here's a blue print of our fuel cell and the LVLP collectors and some photo's.....

KMP 259 Phase 2

Go down about half of the page post # 347

Morris

Unless you're doing big time racing, like Morris does, this might work well for you. It's not particularly cheap. But it is easy and simple.

Phantom Fuel System*|*Aeromotive

thanks for your help guys,
we currently are using a merc fuel pump dont no the exact details of it, but it does produce enough fuel pressure and so on, if i can keep that then run this after it would i be heading in the right direction?
Polished 2 5LT Surge Tank Bosch 044 Fuel Pump Purple Fuel Pump Bracket | eBay

thanks

Fuel Surge
 

That tank is a little small if you are making big HP

You need a high volume low pressure fuel pump to feed the surge tank. use the merc one to run from the surge tank to the motor and buy a carter low pressure fuel pump designed to be used with a carby engine to pump the fuel out of your big tank into the surge tank.

That system looks excellent!

Forget what I said before.....

Just buy this thing!

This is the surge tank in the bottom of the Absolute Pace 427 fuel tank.

I am not sure what the set up is inside the tank though...

Tony

I don't believe that is a surge tank. I believe that is a collector. A surge tank has it's own fuel pump.

I use a fuel cell with a collector. I can almost run the tank dry, and it won't starve in the corners.

Hi Bob

I knew Craig said more about it, I was trying to take it all in...

So this collector means you do not need a surge tank. Is that right?

Tony

Probably. The collector is like a box that surrounds the fuel pick up, and has flap type doors - like a road racing oil pan. Like the oil pan, it helps to trap fuel around the pick up, so it doesn't go lean. My SA110 has a collector, and I can run the tank almost dry before is sputters in a corner.

A surge tank is another small fuel tank mounted near the fuel rails, in the engine compartment. That tank is fed by a low pressure pump. The surge tank has it's high pressure pump (for EFI) that will feed the fuel rails. I think this system is in very limited use, as I'v never actually seen one.

If you mount the surge tank in the back of the car, all you've done is create an external collector. Not sure there's a lot of value to it, considering the cost, complexity, and weight added.

Surge tank location
 

The last thing I would want is the surge tank and pump in the engine compartment absorbing engine heat. My surge tank is in the trunk, the Bosch high pressure pump is located by the side of the LH frame rail so the rail protects it. The high pressure line feeds both fuel rails and then a pressure regulator on the dash returns fuel to the surge tank. A low pressure pump is located by the fuel tank and feeds the surge tank. Think of it as a dry sump for your fuel system. PS my dry sump is also in the trunk for the same reason, reduced heat, both systems work perfectly. A collector holds very little fuel, my surge tank holds about 2 gallons guess which one will run longer in a high speed corner.