Fuel swirl pot

[Fairlineguy]

I am at the point of installing the fuel supply system.

Do I need a swirl pot set up for road use? I am only planning mild running up to 320bhp

[seattlejester]

Lacking information.

 

Car? Use?

 

In general no, if you have a high capacity pump and good diameter fuel lines you do not need a swirl pot.

 

If you have an earlier car and are running the 1/4 inch diameter stock lines and do not plan on replacing them then yes, you will need a swirl pot. Granted unless you had the electronic pump fitted you wouldn't have a way to fill a swirl pot as the mechanical pump is driven by the cam. Which would mean cutting or modifying the factory fuel system anyways to fit an electronic pump at which point you might as well just pull out the stock lines and replace them with larger diameter lines and a high capacity fuel pump and forgo the swirl pot. Alternatively if you do not have a baffled EFI tank and do not plan on modifying the stock one a swirl pot may be beneficial if you plan on doing hard braking and hard cornering.

[Neverdone]

The stock tank won't work.

 

1)Modify it (add baffles, add pump, add correct ports)

2)Get a new EFI friendly tank

3)Run a swirl pot/surge tank, in which case you'll still need to run a low pressure fuel pump from it anyway just to keep it full of gas.

 

All options have their pros and cons.

[TimZ]

The stock tank won't work.

 

1)Modify it (add baffles, add pump, add correct ports)

2)Get a new EFI friendly tank

3)Run a swirl pot/surge tank, in which case you'll still need to run a low pressure fuel pump from it anyway just to keep it full of gas.

 

All options have their pros and cons.

 

If you're going to cut into your tank for any of these solutions, you might consider this:

https://www.holley.com/products/fuel_systems/hydramat/

 

It's more effective than baffles or a swirlpot/surge tank and MUCH easier to install (assuming you have to open the tank up anyway) and much simpler than multi-pump solutions.

[wrcbonk]

As Neverdone and Seattlejester indicated there are pros and cons to each setup. I went with an external system. It has been working without issue for 4+ years in my RB25DET/S30. There is enough room back there to mount everything and I used the existing factory wiring (hot Green wire and Black chassis ground). Both the low pressure supply clicker style pump and the Walbro EFI pump work great and don't get hot. I have never had the fuel cut in a corner (street use only). The Walbro fuel pump whines under normal operating conditions. My understanding is that the Bosch is more expensive and quieter, spend the money. I am using the small BC Broncos swirl pot which doubles as a filter.

 

Internal pumps are industry standard because the fuel cools the pump, but you must modify your tank. No problem if you know how to modify a thin steel tank, go for it (and many people on this site have those skills), but imagining you will find someone or a shop to modify your fuel tank maybe wishful thinking. 

 

Regardless you must have a properly sized return line to keep everything in balance. I replaced the 1/4-inch line with a 5/16ths and used the upper 3/8ths vent port on the tank to return the fuel. TonyD points out you can use the fuel vent line (5/16ths or 3/8ths) as your return that runs from the from the back near the tank to the engine bay, as long as you are willing to reconfigure your fuel vapor system after that. 

 

 

 

 

[Fairlineguy]

Sorry guys I didn't give enough info when posting

Car is a 240z standard fuel tank.

Engine rb25det standard

Using 8mm supply and return pipes

Planning on using in line high pressure pump

Was kind of thinking that as I will only be using on the road and probably always with a 1/4 tank of fuel min

Do I really need a swirl pot set up

Mind you wrcbonk you set up look nice and compact don't think I have seen that filter/ tank here in the uk?

[Neverdone]

Do I really need a swirl pot set up

 

No.