walbro 255 inline pump is fine...you can use the tank vent line as the return but you need to vent the tank somehow. I drilled a hole in the gas cap to vent it...
Don't have any issues with the inline pulling fuel out of the tank? It's always been my understanding that in order to have an inline pump pushing fuel to the motor, you'll also need a pump in tank to pull fuel from the tank to the inline pump. Same concept as the fuel systems on 90's ford trucks that use an inline high pressure pump and a low pressure intank pump.
been runnin that way for 7 years with no issue, just place the pump close to the tank and as low as safety allows.. on my pinto wagon I have the pump in front of the rear axle with the fuel line going to the tank following the wheel well shape so when I shut it off fuel cant return to the tank and the pump stays wet... I did modify the pickup so it sits near the back of the tank further to keep it from starving under launch.. also with a stockish setup, a f150 pump is a pretty good piece, they are 190lph pumps, twice what the 80s ford cars had at only 88lph..
If you remove the fuel hose from the pickup at the tank when it's not empty you'll see that you don't have to worry about pulling fuel out of the tank provided that you mount it low. The pickup itself sits very low in the tank and unless you let yourself run out of gas gravity will do the job for you. Good post by 4cammer72 above.
Well....you could replace the tank with a Fox tank, run wire for a stock pump and use that. Only 2 issues with doing that: first is how you want to run your exhaust. If you run dumps before the axle you're fine. Dual exhaust exiting the rear of the car will be damn near impossible. Second is the filler tube, Fox and II tubes are different sizes. Oh, and tank straps, but that is kinda minor. Here is a vid (my car isn't fuel injected, but you should get the idea):
Ah thats right. I haven't been under the II in a while but I do recall the pickup being lower on the tank compared to the EFI stuff out there. Excellent info, thanks!
It's the frame-mounted electric pump used on EFI Rangers and F150s, and is capable of the correct amount of pressure and flow for most EFI setups. You can get it at Autozone, Advance, or O'Reilly pretty reasonably, or here it is at Amazon. http://www.amazon.com/dp/B000C1KHJG/?tag=stangnet-20
Simply mount it with hose clamps or get a coil bracket, or that bracket they use on posts for chain-link fence, mount it as close to the tank as you can, get power to it (safely, use at least a fuse and a relay triggered by the key, an oil pressure or inertia switch added in would be better) and then run a return line using something like this http://www.summitracing.com/parts/MOR-65385/ and you're done. That's how I did it when I mocked it up in my '76, but I never got around to installing the computer and harness, and the car is sitting half-finished.
or... find a 5.0L fox tank with the fuel pump stand in place. take the 2 tanks to any radiator shop. have them cut the Fox tank 6" square around the fuel pump stand. then right over the MII top vent hole, center the 6"x 6" graft, weld the Fox stand in and get all you need in one stop. OE stand with up to 300lph in tank pump (cooler, longer lasting), OE float that works with your gauge, and return line where it should be, not heating the return side forced into the tank somewhere. $100 labor tops.
I've tried the on-frame/inline pump set up, and for all but a stock 5.0L they heat up. If you live south or in humidity, cavitation & vapor lock are issues. Just my experience.
The OE MII tank is a decent size and add a V-8 Aux tank at the fuel neck in the quarter panel and you have plenty of cruise distance.
I've supported 550rwhp SEFI with the MII tank & fox stand. Add -AN adapters at the pump stand and an upgraded 1/2" stand/tower assembly and good to well over what our beloved MI chassis can handle...