Quote:
Originally Posted by Josh69
Greg, do you think welding in a sump to our stock first gen tank is adequate? I know it'll be 'covered' more often than the factory pick-up, but would it still uncover under normal aggressive street driving/cornering at speed with less than a quarter tank?
I can't decide what to do. I want to run EFI, but I have heard that on the Spectra tanks the sender is in the return sump so it always shows a half tank of fuel until all of the sudden you run out! 
There is a large gas tank repair shop here in town that would weld in a sump and seal my tank. I wonder if they could weld in some baffles on either side of the sump to keep fuel in that area under cornering. |
Well -- let's first establish that I am no "expert" on this - or any other subject for the matter... LOL
A "new" OEM factory EFI car uses an in-tank pump with a "sock" filter over the pickup tube - and they all have some fashion of a built in "sump". I was helping a buddy on his El Camino tank the other day - we were replacing the stock pump. This tank had a PLASTIC sump that oriented the sock and pickup tube. I was surprised at how shallow it was... maybe only an inch deep... and it sat in a baffled area in the bottom of the tank.
What I'm going to do is to ADD ON a sump -- after I cut some holes into the bottom of the existing tank (probably a series of half inchers) - so the fuel will fall into the sump area. So the sump will be a "wart" on the bottom of the tank. I will install weld in bung at the bottom REAR of this sump area for the fuel outlet. So if I build the sump 10" wide (side to side) and build it so that it is a triangle shape (looking at it from the side) tapering from the front area and getting deeper at the back -- figure I'll drop it 3 or so inches at the pickup point... BY THE WAY -- they sell a pre made sump like this at Summit Racing - but they're just steel - but poke around their site and you'll see what I'm making. I'll do mine custom (I like building stuff like this!) out of SS to match my tank...
NOW -- Second issue -- AERATION of the fuel from the return line.... this is B A D... You don't want to be creating a "fountain effect" in the fuel tank... and making pretty little bubbles... which will then get sucked up in the pump. Pumps like liquid and not air! LOL --- so I'd put the "return line" as your old abandoned pick up line... it should be inserted into the tank near the bottom... and thus = should be covered by fuel most all the time... and shooting the fuel at the bottom should keep if from causing this problem.
Place the SUMP/PICKUP area away from the "return" fuel.... most of the old stock tanks pick up fuel from the center area of the tank -- so if that's your return - then you add a sump at the very rear bottom of the tank - you should be golden.
Maybe some others will pick up on this thread and correct any - or add to any - info I'm providing.