fuel tanks for efi

ppyvabw · Post by **ppyvabw** » Sun May 25, 2008 8:25 pm

Is there anything special about an efi fuel tank. If I convert to EFI, will I be able to use my current tank? I know I will have to fit a different pump and filter it well. My current tank doesn't have a gauze inside, but it has a filter before the pump.

Post by **Coops** » Sun May 25, 2008 8:46 pm

efi tanks have a swirl pot inside. stops the pump from loosing fuel. under cornering accelerating and braking etc,
you can use your tank but fit an external swirlpot

ppyvabw · Post by **ppyvabw** » Sun May 25, 2008 8:53 pm

Cheers. Would I just stick with my current fuel line just put in a higher pressure pump? It's only 8mm at the moment. Also, I need to add the return line don't I?

I notice on msn your axle ran out of oil? Has it shagged it? Mine did that about 18 months ago when I was giving it some big licks down the a1. Spat all its oil out a rusty hole in the diff cover.

Post by **Coops** » Sun May 25, 2008 9:05 pm

i run a nylon (plastic) fuel line used on fuel injected capri's,

will let you know tomorrow if the diffs shagged,
if it is thats another thing to add to the clutch problem,

Post by **katanaman** » Sun May 25, 2008 9:28 pm

You will need to run a return line as well to either an external swirl pot or to the tank.

ChrisJC · Post by **ChrisJC** » Mon May 26, 2008 7:57 pm

I'm using a Diesel fuel tank unmodified in my V8 van. It already had the outlet & return pipes, I just put an EFi pump & filter outside the tank.
I don't have a swirl pot or anything like that (as far as I know!), but then I don't corner hard....

Chris.

Post by **katanaman** » Mon May 26, 2008 9:11 pm

diesel tank has a swirl pot built into it. if you get air in a diesel system it stops and wont go again untill its bleed. well most systems anyway although there are acceptions.

chodjinn · Post by **chodjinn** » Tue May 27, 2008 10:26 am

if its an MGB tank all I did was swap out the sender for the later spec one, which has a pick up pipe build into it. You can then use that to feed the pump(s), and plumb the return line into the original pickup. Cost me about £13 to do, and works a treat, hopefully!

ppyvabw · Post by **ppyvabw** » Tue May 27, 2008 12:16 pm

I was going to say the same thing about the diesel.

It is in an MGB, but it's a custom tank that I made. I guess I could modify it and risk being blown up, make another one or just used an external swirl pot.

Ian Anderson · Post by **Ian Anderson** » Sat May 31, 2008 7:17 pm

Use a separate swirl pot

But then you also run 2 fuel pumps

1 low pressure one from tank to filter to swirl to return to tank - needs to flow about 1.5 times your expected use of fuel (to allow time when it plays catch up and pumps air)

Then a HP pump running from the swirl to the fuel rail and back to the swirl.

Remember the 2 fuel pumps will use twice the electricity and need wiring able t take the load.
Ian

ppyvabw · Post by **ppyvabw** » Sat May 31, 2008 9:55 pm

I'd thought of that, yeah.

In that case, can I not have my low pressure pump pump fuel into the engine bay, say my current carb pump and fuel line (maybe a bigger version tho) then have the swirl pot and high pressure pump in the engine bay. Just cuts down on wiring and plumbing and the load issue you mention, i can just a live off from somewhere.

ppyvabw · Post by **ppyvabw** » Sat May 31, 2008 10:22 pm

Does the return line from the fuel rail need a restrictor in it? If it didn't wouldn't it just piss fuel out the return line and there would be no pressure.

Post by **katanaman** » Sat May 31, 2008 10:23 pm

Thats why EFI systems have a fuel pressure regulator built into them.

ppyvabw · Post by **ppyvabw** » Sat May 31, 2008 10:39 pm

ooooooo, I see. Is that the thing on the fuel rail that looks like a small fuel filter?

Am very ignorant about fuel injection never having used it before. If anyone can recommend and good books on it or websites, i'd be gratefull.

Post by **katanaman** » Sat May 31, 2008 10:42 pm

Yep thats the chap. Don't know of any books but there is a lot of good stuff over on the MS forums. Different ECU but most of the rest of the system is the same.