Fuel tank differences apart from the obvious

[e30-EVN]

Evening,
I'm about to take on the task of removing the whole rear beam to do an overhaul and at the same time drop the fuel tank and give that a going over too...

The car was originally a 1990 316i and has the feed pipe on the bottom from one side to the other so from what I can see is the smaller capacity tank.
Does my tank have a swirl pot inside? Or do I need to buy the larger tank?
Cheers

[Brianmoooore]

If the car was an 'i', then it will have the swirl pot, with the returning excess fuel from the engine's injector rail, being deposited into it via the second pipe on the fuel pump.
Your tank uses the fuel in the left hand side by it flowing through the small pipe joining the two sides together at the bottom. The larger tank uses an internal siphon pipe to move fuel from left to right, primed by the returning fuel.

[e30-EVN]

If the car was an 'i', then it will have the swirl pot, with the returning excess fuel from the engine's injector rail, being deposited into it via the second pipe on the fuel pump.
Your tank uses the fuel in the left hand side by it flowing through the small pipe joining the two sides together at the bottom. The larger tank uses an internal siphon pipe to move fuel from left to right, primed by the returning fuel.

Thank you Brian, yes the car was a September 1990 316 i so i can keep my tank than and simply drop it down to refurb and treat it

[Brianmoooore]

Yes, existing tank and pump will be fine for everything except engines that need exceptionally high fuel pressure.

[e30-EVN]

Yes, existing tank and pump will be fine for everything except engines that need exceptionally high fuel pressure.

I have carried out m60 v8 swap but that will be no worries for this setup thanks again mate

[BenHar]

Yes, existing tank and pump will be fine for everything except engines that need exceptionally high fuel pressure.

I have carried out m60 v8 swap but that will be no worries for this setup thanks again mate

I think the extra 8 litres in the larger tank might help you go a couple of miles futher on a tank full.

Ben

[e30-EVN]

Yes, existing tank and pump will be fine for everything except engines that need exceptionally high fuel pressure.

I have carried out m60 v8 swap but that will be no worries for this setup thanks again mate

I think the extra 8 litres in the larger tank might help you go a couple of miles futher on a tank full.

Ben

You may be right but I think my point was more are there any differences internal of wiring and pipes etc. If mine has swirl pot inside which brings cleared up it does, I'll keep mine. I think with a v8 in there I'm going to be at the petrol station quite often anyways so an extra 8 ltrs wont help much