Hi everyone! I had a lot of questions on how I installed a Fox tank in my Cobra on youtube, so I went ahead and shot a video and posted it. If anyone is interested, here is the video. Sorry about my narrative skills and some of the shots. Hope this helps some people out.....
I haven't thought too much about this in a long time.... but if anyone decided to do this you could probably forego some stuff if you were to purchase a new tank. Here are my suggestions:
At the time I did it, there was no replacement tank available for the II. From what I've found when upgrading my fuel system to support fuel injection, the early Fox cars used the same ohm scale for the sending unit, so I'd suggest just buying a new sending unit for a 79-84(?) car and installing it for your gauge to work. Much easier than modifying the II's float.
If you go with a Fox tank like I have, you may be stuck doing some of the same stuff I had to as far as the fill tube goes. Maybe you'll have better luck finding an adapter or appropriate fill tube than I did so you won't have to weld there. If not, you may be farther ahead to cut and weld that section. Remember that you may want some kind of fuel tank sealer like Red Kote.
You'll have to figure out a pickup for your application. I'd suggest just using an electric in-tank pump with a pressure regulator and just go that route - that would save some welding and potential leaks. But you'll also have to wire a relay to run the pump. At the time I installed this tank I was still using a mechanical pump and had no interest in wiring anything. But, times have changed, haven't they?! Honestly, wiring a fuel pump is FAR easier than everything I did to make this work. And, if you go down the same path that I did, let me tell you that having that electric pump in place already would've been so handy! You may find it worthwhile to upgrade your fuel lines as well - you'll definitely want high pressure connections from the pump to the regulator anyway, so I'd highly suggest doing it now.
As you can see, this can turn into a rabbit hole pretty quick! But I have to admit that I'm glad I did it - it made upgrading from a carb to fuel injection an easier project than it might have been without. Now, I think the worst part of it all is figuring out what to do with your exhaust if you don't want to run dumps. Having the fuel tank run the entire width of the rear of the car kind of inhibits running exhaust pipes to the rear of the car - it's just something else to think of if you decide to go down this path.
If I ever went the F.I. route, I was think of using a surge tank with the pump in it so there wouldn't be a need to touch the main tank or install a return line and I already am running a Holley blue pump. The Holley pumps the fuel to the surge tank and the high pressure pump in that tank feeds the F.I. The fuel is recirculated to the small tank.
If I ever went the F.I. route, I was think of using a surge tank with the pump in it so there wouldn't be a need to touch the main tank or install a return line and I already am running a Holley blue pump. The Holley pumps the fuel to the surge tank and the high pressure pump in that tank feeds the F.I. The fuel is recirculated to the small tank.
That's definitely an option as long as you have a good tank. Mine was Swiss cheese and there was no new replacement tank available at the time. I ended up picking up this used tank from a salvage yard, so it was a pretty cheap fix - even with the modifications I had to do to make it work. Obviously, it's not for everyone, and there are a number of different paths one could take. But going this route ended up making things easy for me to convert to fuel injection when the time came.