The V8 Owners Forum -

I have 3.9 V8 EFi which has a couple of solid lines with braided 6" connectors to allow some flex I guess? One supplies fuel from the std pump in the tank, with the other returning it back to the tank.

I have had problems with fuel starvation when the vehicle is tilted to around 45 degrees. It will run for 30-45 seconds and then stall. It has to be winched to the hortizontal on the slope, started and then 'unwinched' back to 45 odd degrees.

I'm thinking about a swirl tank like this...

https://fitechefi.com/product/force-fuel-system/

The question is the 50004 has a feed from the tank and a return. It then has a single petrol feed to the EFi and no return. Is it okay to just blank the return feed on the engine?

That's very expensive, have a look at OBP https://www.obpltd.com/product-category ... wirl-pots/

A return form the fuel rail keeps the fuel in the rail cooler. You need one if the rail is designed that way, otherwise you're just going to trade one problem for another.

Ultimately, this tank will mask the true problem that your fuel pump in the tank is not up to the job. This will let the engine run when it's given up, but only for the duration of the content of the pot.

Nords wrote: ↑Sun Sep 21, 2025 5:47 pm I have 3.9 V8 EFi which has a couple of solid lines with braided 6" connectors to allow some flex I guess? One supplies fuel from the std pump in the tank, with the other returning it back to the tank.

I have had problems with fuel starvation when the vehicle is tilted to around 45 degrees. It will run for 30-45 seconds and then stall. It has to be winched to the hortizontal on the slope, started and then 'unwinched' back to 45 odd degrees.

I'm thinking about a swirl tank like this...

https://fitechefi.com/product/force-fuel-system/

The question is the 50004 has a feed from the tank and a return. It then has a single petrol feed to the EFi and no return. Is it okay to just blank the return feed on the engine?

There are many swirl tank setups available. Just watch as the likes of that Fitech does not adjustable fuel pressure, if that matters to you. Given it's aimed at probably teh LS market, it could well be a static 60psi reg.
No big deal really, but would require re-tuning for your car.

Radium, Nuke, 034 Motorsport all make nice surge tanks. Although really you would not need anything more than a simple Walbro 255 or equivalent.

There are of course many chinese/cheaper surge setups, but one with an in-tank pump inside the tank will be neater and easier. Up to you what space you have available, and whether you want to use a reg on the fuel rails, or re-locate this to the new setup as that Fitech does ( would typically be a dead and fuel rail setup )

scudderfish wrote: ↑Tue Sep 23, 2025 5:39 am That's very expensive, have a look at OBP https://www.obpltd.com/product-category ... wirl-pots/

I would not bother with any that then rely on an external pump. Just gets messy with lots of hoses and fittings, and takes up more room anyway

Whilst Nuke or Radium, well renowned brands would be preference...they are a bit pricey.

Speedingparts lists a few more chinese style at fairly ok money

https://www.speedingparts.co.uk/c/fuels ... McbQ6H6l1e

eg

https://www.speedingparts.co.uk/p/fuels ... McbQ6H6l1e

Thanks guys,

That is really useful. It is a standard 3.9 EFi running a K&N and open pipes, on a std pump mounted in the tank. I do have a pressure gauge for the ‘rail’ on the block but never tried it before the line failed. Both supply and return lines have been taken out of the car now.