Russell Performance Tubing Cont'd

[Paul Gayter]

For those who remember the last thread.

I completed the fuel system on Friday made entirely from thick wall copper tube. The tube nuts and sleeves were about 1.50 each so the whole job did not cost that much. I had to remove the acoustic mounts due to the possibility of tube fracture and incorporated some movement bends to allow for pump vibration and bodt flex. All done!

The time taken however was costly. The new system does not smell at all which is a result. Attachments show new system and fittings and tube I have had to disgard thanks to Russell Performances policy of witholding critical safety information.

Damn their eye's!!

[Ricky]

Originally Posted by Paul Gayter

For those who remember the last thread.

I completed the fuel system on Friday made entirely from thick wall copper tube. The tube nuts and sleeves were about 1.50 each so the whole job did not cost that much. I had to remove the acoustic mounts due to the possibility of tube fracture and incorporated some movement bends to allow for pump vibration and bodt flex. All done!

The time taken however was costly. The new system does not smell at all which is a result. Attachments show new system and fittings and tube I have had to disgard thanks to Russell Performances policy of witholding critical safety information.

Damn their eye's!!

Very nice.... wanna sell your old pipes?

[Martyn-ak427]

Hi Paul,

Looks pretty good. I will soon be doing the fuel system installation on my AK & will also being using a Fram fuel filter but can I ask why you have two?
Hopefully not to much of a daft question.

Regards,
Martyn

[Paul Gayter]

Hi Martyn,

No question dafter than me!

The reason for two is that I have fuel injection fitted. There is no problem when the tank is full but when you get down to half or less full is is possible for the fuel to swill away from the pickup in the tank.

With a carb you have a fair reserve of fuel in the float chambers and line. This means that under cornering if the fuel swills away from the pickup in the tank there is enough in the lines and carb to sustain throttle for a few seconds. Thus one fuel circuit is enough.

With fuel injection the fuel in the High pressure circuit is constantly flowing back to the tank via the fuel pressure regulator. If the fuel goes away from the tank pickup air is presented to the injectors which causes the engine to momentarily cut out. This is undesirable!

To get round this you install a second fuel tank smaller than the first which you ensure is always full using a second low pressure pump. That acounts for the second filter which is simply ensuring that gurt lumps of muck don't muck up the nice low pressure pump. The HP pump takes its fuel from the secondary tank sometimes know as a swirl pot.

[Martyn-ak427]

Many thanks Paul & good luck.

[Colin GD427]

Hi Paul
Your system looks very good. I have been told yesterday that it is recommended to have the pump external for cooling, and below the tank. My pump and swirl pot are very near the bottom off the boot(inside). Whats your ideas on this. The one thing which does anoys me is the noise of the pump (is mounted on rubber, 3mm thick), but it does not do it all the time.

[Paul Gayter]

Hi Colin,

Hum.. Yes..

Well my HP pump is wrapped in a foam sleeve so I doubt that being outside would make that much difference. In a perfect world you would have the fuel as cool as you can get it. Snag is that as it is pumped through the injector rails it picks up heat from the engine. On a long run my main tank is warm to the touch.

My HP pump is always below fuel level as the swirl pot is mounted high. I mounted it between the roll over bar fixings because it is dead space and keeps the fuel head high.

With regard to pump noise there is little you can do if you use rigid line like wot I have. If you use flex then you can use AV mounts the like of which I have just removed.

In fairness once the engine is running you can only hear the pump when the engine is on tickover so its not such an issue.

There are always things you could have done better with kit car builds but when you only get the one shot at it its hard to achieve perfection.

If your system works OK why change it, sounds perfectly alright to me. The HP pump will always be below fuel level as long as it is not higher that the swirl pot so pump position is less of an issue. I prime the swirl pot with the HP pump OFF when I have to drain the system.

I made a cover for my system out of 12mm Plywood so that loose items flying about in the boot will not damage the tubing. (attached)

[Happy Jim]

Paul,

I'm about to do mine in just about the same way as yours. I've got a 1.5ltr swirl pot...what have you done with the vent pipe on top?

Rgds

Jim

[Paul Gayter]

Hi Jim,

I don't have a vent pipe at the top, the uppermost connection is the LP feed to the tank.

In a perfect world this feed to the main tank would be the highest point in the Swirl Pot but height contraints meant a side exit.

The Lowest connection is the Feed to the injection pump, two connections about 2 thirds up are Return From Injector Rails and infeed from LP Pump to keep Pot full.

I don't think that there is any real importance to the positioning of the feeds but the exit to the main tank should be at the top and the exit to the HP Pump should be at the bottom.

The swirl pot really does make a difference when you are going round long sweepers at a lick, without it engine cut out is very likely on injected systems. Also though less important the engine will cut out under braking.

If you can then, use the vent connection to return to the main tank. One thing you have to watch is the configuration inside your swirl pot. I have seen designs where the returns have a horizontal bend inside the tank to cause the returning fuel to make a swirl (hence the name I guess) inside the pot. Other pipes may also do things that cannot be seen from the outside like extending down and picking up at a low point. Its the sort of thing that could spoil you day if you were unaware of it.

[Happy Jim]

Many thanks Paul

Jim