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Swirl Pot - is it needed?
cps13 - 8/12/10 at 11:13 AM

Hi all,

I am building a locost which will be a road going car. I will probably take it on track days maybe 3/4 times a year at most.

It is going to have a 1.8 zetec, EFI. The question I have is do i really need a swirl pot?

i don't want to run the risk of damaging the engine but don't want to install unecesasry parts.

Cheers,

flak monkey - 8/12/10 at 11:44 AM

Yes you do, unless your tank has one built in.

BenB - 8/12/10 at 11:49 AM

Some people run without them and seem to get on okay but I think it's a cheap insurance to have. Blatting round a high speed corner at full chat and going all lean might be an expensive problem compared to a cheap swirl pot. Just make sure you don't recirculate back into the swirl pot otherwise you risk making toasty warm fuel and vapour locks etc etc. Best to feed the return back from the fuel reg to the tank.

SPYDER - 8/12/10 at 11:51 AM

Hi there. My friend has a factory built Zetec engined Westfield that suffers awfully from fuel starvation if its tank is less than half full. He is going to mod the tank. I would advise you to do the same.

cps13 - 8/12/10 at 12:49 PM

quote:
Originally posted by BenB
Some people run without them and seem to get on okay but I think it's a cheap insurance to have. Blatting round a high speed corner at full chat and going all lean might be an expensive problem compared to a cheap swirl pot. Just make sure you don't recirculate back into the swirl pot otherwise you risk making toasty warm fuel and vapour locks etc etc. Best to feed the return back from the fuel reg to the tank.


Thanks for your answers guys - will be fitting one.

The setup i was planning is...

tank----l/p pump----swirl----filter----h/p pump----fuel rail----pressure reg----swirl pot----tank.

Are you saying take out the feed from the fuel reg to the swirl pot? Would you just blank out one of the inputs to the swirl pot because I understand they come with 4?

Cheers,

flak monkey - 8/12/10 at 12:54 PM

I always ran with the HP return to the swirl pot. No problems.

If you do run the return back to your tank, make sure your LP pump can supply at least the flow rate of the HP pump.

l0rd - 8/12/10 at 01:03 PM

and i would use a LP filter before the LP pump to ceap it nice and clean

SPYDER - 8/12/10 at 01:49 PM

quote:
Originally posted by l0rd
and i would use a LP filter before the LP pump to ceap it nice and clean


Please be careful if you fit a filter before the LP pump. We had a high RPM misfire on our TR7V8 racecar which was eventually traced to air being drawn in at such a fllter.

beaver34 - 8/12/10 at 02:29 PM

ive fitted one, my tank was baffled but i had fuel stavation less than 1/2 a tank on roundabouts

Ivan - 8/12/10 at 02:40 PM

In hot climate overheating fuel is a definite problem that causes fuel pump failure amongst other things, so in hot climate definitely return feed into tank and not into swirl tank. Also in hot climates run with your tank as full as possible and top up as often as possible. (by hot I mean > 38C). (Doubt if that's a problem in England). How do I know this - I have paid the price of expensive fuel pumps a couple of times on the tintops. Insulation between tank and hot road plus fuel cooler also helps in these circumstances.

If you have good baffling in the tank I really don't see the need for a swirl tank, but then I am no expert.

v8kid - 8/12/10 at 02:55 PM

make sure the Lp pump pumps at a higher rate than the Hp pump or the swirl tank will run dry. Guess how I know

RazMan - 8/12/10 at 04:19 PM

If you fit a Landy pump in the tank you get the pump, swirl pot and sender all in one - much easier IMO

steve8274 - 8/12/10 at 04:30 PM

i hadnt considered a swirl pot.
what is required to use them, ie swirl pot?
how much will it all cost roughly?
is it cheaper to put something in the tank and if so what?
sorry for all the questions
steve

cps13 - 8/12/10 at 05:23 PM

quote:
Originally posted by steve8274
i hadnt considered a swirl pot.
what is required to use them, ie swirl pot?
how much will it all cost roughly?
is it cheaper to put something in the tank and if so what?
sorry for all the questions
steve


The point of a swirl pot is to keep constant supply of fuel to the engine. Fuel starvation often happens during high speed cornering, especially when the fuel tank starts to empty. They are often included inside the tank and therefore no external one is required. However I have heard stories, even on this thread, of an external swirl pot still being required.

To have a swirl pot you will only really need an additional low pressure pump and filter to be installed between the fuel tank and swirl pot. All other components are needed anyway.

swirl pots start at around £45, if anyone has found cheaper please let me know!? About the additional cost of a tank with a built in device I believe.

mccsp - 8/12/10 at 06:41 PM

RazMan,

Do you know the part number of the landrover fuel pump system. ANy idea of dimension, interested in fitting one to an MK 6gallon fuel tank.

Cheers

RazMan - 8/12/10 at 10:15 PM

I used this one

RANGE ROVER P38 V8 IN-TANK FUEL PUMP`94-`98 on eBay (end time 23-Dec-10 14:56:39 GMT)

PART Nş: STC4344

It has a telescopic sender which sits on the bottom of the tank - quite a neat little system really. Pump gives me 3 bar and plenty of flow.