Swirl pots

[George_Of_The_Jungle]

Hey guys, was at silverstone yesterday, and suffered huge amount of power loss going through right hand bends (with 3/4 full tank), was recommended looking into swirl pots to fix the fuel surge issue. Any idea on costs, which makes to go for?

Complete novice bit now.
Where do i put it

many thanks
George

[handpaper]

You should only start getting fuel starvation issues on looooong right handers with about 1/4 tank left. I'd suspect a contributory fault of some kind.
If you do fit one, pretty much anywhere outside the cabin - on the left chassis rail under the bonnet is a nice accessible spot.

[UweM3]

You should only start getting fuel starvation issues on looooong right handers with about 1/4 tank left. I'd suspect a contributory fault of some kind.
If you do fit one, pretty much anywhere outside the cabin - on the left chassis rail under the bonnet is a nice accessible spot.

agree. Maybe lift pump dead?

I have my swirlpot in the boot. Isn't mounting the swirlpot in the engine bay away form the tank ( and the main pump) resulting in a LOT of pipework?

[Theo]

Mines also in the boot, fed by a standard E30 M3 low pressure lift pump. Had it made by Nigel, think his username on here is alloyproducts or something like that.

[MillRat]

Mine is like this, sort of ^^

I just moved the whole fuel pump assembly from behind the rear wheel and fitted it to the boot. One day I will change it to the above design (easier to access the fuel pump(s)).



EDIT;

After fitting my swirl pot, I discovered that my pick up pump was dead. I am not saying the swirl pot was a waste of time (it means I can run far less fuel during a track session), but I probably didn't need to fit it when I did (I only needed to replace the in tank pump).

[agent006]

I was talking to a fellow E30 driver at Colerne in June and he mentioned that he had the return fuel line terminated across to the other side of the tank. Something to do with it then being right by the fuel pump.

Does this make any sense? Was right at the end of the day so it's all a bit hazy.

[MillRat]

All the fuel lines originate and terminate at the same point (the fuel level sensor/in tank fuel pump assembly). Makes it very easy to find all the fuel lines.

[Black_Potato]

Is it a competition car?

If so you should check the regs as I think it needs to be sealed of from the cabin so you will have to plug up the fire wall if you leave it visible.

Most the racers use the spare boot well and put a metal disc over it.

Another option if its just for trackdays or in a race series that allows it is to have the fuel tank cut in half so you just keep the big bit. Should give you around 40ltrs capacity and greatly reduce the fuel surge whilst reducing the weight a bit as well.

[George_Of_The_Jungle]

The cars is close to standard, and is for road use. I have only used it at the track once. I have been experiencing the fuel surge on the road but typically below 1/4 of a tank.

Cheers for all your input guys, I will look at getting a new pick up fuel pump first and see if that resolves the problem.

Many Thanks
George

[UweM3]

The cars is close to standard, and is for road use. I have only used it at the track once. I have been experiencing the fuel surge on the road but typically below 1/4 of a tank.

Cheers for all your input guys, I will look at getting a new pick up fuel pump first and see if that resolves the problem.

Many Thanks
George

Examine the lifter pump assy carfully. A fellow M3 owner has shown me pictures of his lifter pump with just the ground strap snapped of the carrier. Pump was fine after repairing this.

[Theo]

What car do you have George? Later cars have a single in-tank injection pump so no chance of lift pump failure causing your problem.

[George_Of_The_Jungle]

Hi Theo its a tech 2 sport

[Theo]

In which case you have a single in-tank injection pump.

Fuel starvation with 3/4 tank of fuel does seem odd, I used to get it with around 1/3 or 1/4 of a tank. The swirl pot works a treat and I can run the car with only a few litres of fuel.

[Tommoed]

I was talking to a fellow E30 driver at Colerne in June and he mentioned that he had the return fuel line terminated across to the other side of the tank. Something to do with it then being right by the fuel pump.

Does this make any sense? Was right at the end of the day so it's all a bit hazy.

This sounds like it could've been me?! Sorry if this is a cold thread but I've experimented with all sorts of solutions to this problem.
1st attempt, swapped the in tank pump to one with the fuel return pipe in the top (2 hard pipes coming out of the top, 1 flow, 1 return), capped the return line in the tank on the passenger side and added an extended fuel line to the top of the pump. This puts the returned fuel right where the pump picks the fuel up from.
This was good down to just below 1/4 tank on track. I then fitted new front shocks, front adjustable top mounts and a set of Toyo R888s and suddenly my fuel surge problems came back at about 1/2 tank (I could pull far more force in the corners now obviously!).
I bit the bullet and went for a swirl pot set up. £60(ish) for a 1 litre pot off the net (there's loads available), a sytec external pump off the good old bay of e with some fuel pipe & clips bringing the total to about £150.
Similar set up to the other pics already posted with the pot just behind the rear bulkhead.
I can now run the tank down to the warning light coming on with no hint of fuel surge