www.ColoradoClassicBroncos.com

I'm getting ready to order an EFI tank and I'm not liking the 23 gallon options for height reason's 14.5" vs. 10" OEM even with a 1" body lift I know its only an 3.5" difference and that's with out a skid plate. I've read Gunnibroncos thread and looks like he reduced his capacity to 18 gallons Hoping to hear his comments on the range of just the 18 gallon tank as I will not be using the saddle tank.
Also what kind of fuel mileage might I be getting as I've never owned a Bronco before. 35" tires, 4:88 gears with a 4R70W

My question for everyone is I'm using a 96 Explorer EFI with 302, should I use a 96 Explorer Fuel pump or is there something better for an internal pump set up?

Thanks,
Steve

That's kinda hard to determine your MPG's, but you should be able to get a pretty good guide from others who've done that engine.

Different engine, but I figure 10MPG's (no working fuel gauge) and I know that is probably 50% conservatively, but I don't want to be walking anywhere!!

You're really not leaving much on the table at 18 gal. where stock capacity around 20gal. And with EFI you won't lose any range. I do think the benefits of a shorter tank for an offroader far outweigh the sacrifice of a few gallons. One other thing you may consider is if you push the axle back much at all, you will have an interference with the tank. My plan was to have Aero make a vertical recession in my tank of a couple inches, which should all the axle to be able to move back 3"+/-. I sent them drawings and got a quote back a while ago, but I don't have that handy. I didn't order yet either.

Thanks for the info, I'm losing capacity because of the rear rear stretch I've got the OEM drawing from aero and I have 2 version that I will be sending them in the morning. On my previous rig I always carried extra fuel and will on this one if if possible. I just remember driving a 72 chevy and the mileage it got I swear you could see the needle move, lol

I know a few of us with 302's and EFI get 13-15 mpg on the highway. I get 14 on the highway in my 76 and just about that in my 69. I have a 302 in the 76 mustang EFI, and a 400 in the 69 Holley MPFI. I have easily gone 300+ miles on one tank in the 69, both have the 23 gallon EFI tank.

LandsharkThose are incouraging numbers, I will have aero double check the fuel capacity on my drawings. What fuel pump are you using? And how about the fuel gauge sending unit working with the OEM gauge

The 351 mileage may be suffering from happy foot

Rox Crusher wrote:The 351 mileage may be suffering from happy foot

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Better than mine. Still get's 9mpg even after the efi and 4r70w.

The Aero tank is a nice tank. They did screw up my order on the first try, but fixed it without question. They sent me 2 tanks, one for the in-tank pump & one for external pumps. I ended up using the external pump because I could mount it higher than the internal pump model. If you are ordering it with the internal pump, I'd ask that they recess the pump hanger 1" from the top of the tank (like the sending unit-covered in duct tape in this pic), otherwise the inlet & outlet are above the tank, and require the tank be hung lower.



I like that it sits up quite high, and clearance hasn't been an issue. I had them send the mounting brackets loose from the tank & I welded them on, to make sure the tank was tight to the bottom of the truck.

During this rebuild of my Bronco, I pushed it back further than stock to help with moving my axle back. I have a custom rear bumper, and I was able to push the tank back so it was even with the end of my frame. I probably gained 3 inches or so.

I'd say 13 MPG is accurate, I'm running Mustang EFI, and have never taken the time to really track my MPG.

Gunnibronco,
Thanks for the info on the tank, My plan is to also run the tank back to the end of the frame but will need to cut 3" off the tank to get the stretch I'm looking for or extend it 3 " past the frame "undecided". On your Aero tank did you have them also relocate the fill tube forward?

I had mine built to standard specs (but shallower), long before I moved it back. I didn't relocate the fill neck, but moved the gas cap hole back too. I cut the filler neck and used a generic flexible fuel filler hose, like you'd use under a flat bed on a pick up truck. To move the tank back, I had to remove the front of the rear floor brace.

Some pics of the filler neck, and brackets I added to the frame & how it fit to the tank. When I originally welded the mounting brackets to the tank, I used 2" spacers, because I figured I might end up with a body lift. That didn't happen, but I was able to cut the spacers to fit and keep the tank as close to the body as possible. When I first installed the tank, the body was on the factory (squashed) body mounts. When I moved it back, I also added new mounts (and changed the body mount points entirely), so I was able to cut my spacers, and raise the tank to match.

Gunnibronco wrote:To move the tank back, I had to remove the front of the rear floor brace.

I want to look at this closer! Maybe I don't need a fancy notch??

I don't have a lot of good pics, and the truck is on my trailer at a friend's house out of town. I'm moving to NV in a couple days, and leaving my F250 & 74 at my friend's house. I will return in late September to get it and drive it to NV. I'll be able to get better pics then.

Under the floor at the very back of the truck is a channel (upside down U), I cut the forward most part of the U and folded it up against the floor (you could remove it completely too). That let the tank move back to where you see it in the pic. Not hard at all. Hard to explain though.

I think I understand. You only folded the front part of the channel? Any concerns with a sagging bed? What are the rough dimension of the channel? You mentioned gaining 3", so I assume it's depth is close to that?

I folded it up to the bottom of the floor, drilled through the floor & spot welded it from above. I figured that would help keep the strength. Removing it completely might let the bed sag in the middle. But I think that's unlikely, unless you are hauling super heavy stuff in the bed. My bed had sagged outboard of the bodymounts, I think this happens from running without a top a lot & the truck was really abused before I got it.

Yes the channel is about 3" deep (front to back, not height) and allowed the notch in the back of the tank to move right to the back of the bed, instead of the front of the channel.

Hmmm, so maybe a notch up front for the axle, a tuck in the bottom, and make the tank 3" deeper...and not lose much volume at all??

Yeah, you are probably right. I moved the tank back, but also the axle, and I'm not 100% sure the pumpkin will clear the tank. It won't surprise me if the pumpkin touches the front of the tank when the axle raises to full compression. If your axle is in the stock or 1" back location you'll clear no problem. I pushed the axle back 3.25", by my measurements. Maybe the tank only moved back 2".