Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB GT V8 Factory Originals Technical - Fitting a Swirl Pot in the 'B' tank.

Can anyone tell me how to modify my fuel tank for fuel injection.
I have the Rover SD1 remote fuel pump ( Bosch ) and pipes.
What is the principle of a swirl pot and does anyone have details of the sizes etc to fabricate one.
Where does the fuel return pipe go? I could weld a pipe into the fuel pick-up/sender mounting plate in the side of the tank.
The fuel pump is in the Rover casing with mounting bracket. Any suggestions for mounting position? How close to the bottom of the tank does it need to be?
All advice greatfully received!!


I put the swirl pot in the spare battery well. Check out the feature article of the latest British V8 Newsletter to see how it was done.
Jim Blackwood


A swirl pot is a sort of perforated container - a bit like a collander which sits in your fuel tank. The idea is that when you go round a corner a bit quickly and all of the fuel sloshes to one side of the tank, the fuel in the swirlpot sloshes out rather more slowly as it can only pass through the holes in the sides of the pot. By the time you have finished your corner, the fuel has centralised in the tank and the swirlpot is full again. The fuel pickup is inside the swirlpot and the effect is that when you are running a bit low on petrol, the pick-up pipe is never starved of fuel on sharp bends. This means that the engine never falters through lack of fuel. Useful for carburetted engines and essential for injected engines as they just stop because high fuel pressure is necessary for their running.

My fuel tank was modified on the basis of suggestions from Roger Parker using the swirlpot from a scrapped injected Sierra and a new MGB tank. I used Barfords in Tottenham to do the job and they did it brilliantly and quickly. Amazingly they have gone out of business and I don't know who to suggest to you. A real shame because the companies which have done poor or shoddy work ( and that means most of them)are all still in business.

My fuel pump is mounted under the car high and close to the battery compartment. A word of warning - there must have been some debris from the modification inside the tank and this resulted in two fuel pumps becoming blocked at a very early stage in the trial running of the car. I can imagine that it is very difficult to clear a tank which you have just welded closed and so I would recommend very strongly a pre-filter fitted between the tank and the pump. It can never do any harm.
Marc Gander


Brise (or Brice?) Fabrications in Dartford makes swirlpots and/or can modify your tank. They have experience with race cars. My swirlpot is either in a new tank, or (more likely) in the back of one of the battery bins.
You can avoid damage to your high pressure pump by not placing the pump inside your tank, but first have an in-line fuel filter. They are available with banjo connection and not only prevent against debris, but also against bad fuel. Some even have water-separators.


This thread was discussed between 18/05/2002 and 19/05/2002

MG MGB GT V8 Factory Originals Technical index

This thread is from the archive. The Live MG MGB GT V8 Factory Originals Technical BBS is active now.