Upgrades To Big Blue For Overlanding?

[Gary Lewis]

Good idea, Bill. I actually have one you sent me a few years ago, and could do it like shown below. And, I would put a tank in, probably under the bed, with a pressure switch to bring the compressor in. Plus a switch in the cab to turn it on. But, I don't think I need the in-cab gauge that the Viair system has. However, I will need to figure out where to put a quick-disconnect port.

Bill - Does Darth have dual fuel tanks? How do you have the fuel system set up? What pumps, reservoirs, switching valves, etc? The parts catalog shows a complex arrangement of reservoir, pump, filter, etc on the frame. What do you have and what would you recommend?

[85lebaront2]

Bill - Does Darth have dual fuel tanks? How do you have the fuel system set up? What pumps, reservoirs, switching valves, etc? The parts catalog shows a complex arrangement of reservoir, pump, filter, etc on the frame. What do you have and what would you recommend?

Gary, I used the 1990 fuel tanks and pumps. That is the year where Ford went to high pressure in-tank pumps. Since Big Ugly was a standard cab I had to extend the fuel lines 35" so I bought a Dorman fuel line repair kit which contained bulk line and fittings.

If you can find a 1985.5 to 1989 truck then you can get the 1985.5-1986 in-tank low pressure pumps and use the frame mounted reservoir and high pressure pump. If you use the early pump assemblies the senders will work with the stock gauges. Since I was originally planning on using the 1990 dash I wasn't worried about the change in fuel gauge senders.

 

[Gary Lewis]

Gary, I used the 1990 fuel tanks and pumps. That is the year where Ford went to high pressure in-tank pumps. Since Big Ugly was a standard cab I had to extend the fuel lines 35" so I bought a Dorman fuel line repair kit which contained bulk line and fittings.

If you can find a 1985.5 to 1989 truck then you can get the 1985.5-1986 in-tank low pressure pumps and use the frame mounted reservoir and high pressure pump. If you use the early pump assemblies the senders will work with the stock gauges. Since I was originally planning on using the 1990 dash I wasn't worried about the change in fuel gauge senders.

I have the high-pressure pump from Huck, which is a '90, so could go that way. But, apparently Huck was a single-tank truck as there's no switching arrangement in the lines. And my catalog stops at 1989, so I don't know what parts were used on the later trucks.

But, I know that the 1985.5+ systems were problematic, so wanted to consider the later stuff. What do you have to switch tanks?

[85lebaront2]

I have the high-pressure pump from Huck, which is a '90, so could go that way. But, apparently Huck was a single-tank truck as there's no switching arrangement in the lines. And my catalog stops at 1989, so I don't know what parts were used on the later trucks.

But, I know that the 1985.5+ systems were problematic, so wanted to consider the later stuff. What do you have to switch tanks?

Biggest problem I see will be gauges, Ford changed the gauges somewhere between 1986 and 1989, the change will probably be where the ICVR goes away. The temperature gauge apparently works with either system and the oil pressure changed from being an actual gauge to an "oil pressure indicator" sort of a reverse idiot light but, by cutting the fixed resistor out of the circuit and using the old sender it becomes a proper gauge. The fuel gauges are the problem, older gauges read empty with an open circuit, later ones read beyond full with an open circuit. As far as I know the resistance of the senders changed when the gauges changed so that would be the issue.

As for the external high pressure pump, it was used from 1985.5-1989 after that it is the two high pressure in-tank pumps. The tank switching is just the dash switch and the pump modules have shuttle valves that do the change over. These also had issues, the shuttle valves would stick or leak and cause one tank to return into the other one.

[Gary Lewis]

Biggest problem I see will be gauges, Ford changed the gauges somewhere between 1986 and 1989, the change will probably be where the ICVR goes away. The temperature gauge apparently works with either system and the oil pressure changed from being an actual gauge to an "oil pressure indicator" sort of a reverse idiot light but, by cutting the fixed resistor out of the circuit and using the old sender it becomes a proper gauge. The fuel gauges are the problem, older gauges read empty with an open circuit, later ones read beyond full with an open circuit. As far as I know the resistance of the senders changed when the gauges changed so that would be the issue.

As for the external high pressure pump, it was used from 1985.5-1989 after that it is the two high pressure in-tank pumps. The tank switching is just the dash switch and the pump modules have shuttle valves that do the change over. These also had issues, the shuttle valves would stick or leak and cause one tank to return into the other one.

I'm thinking the 1990+ system is the way to go because I think it would mesh best with the existing plumbing to the fuel rails. But, maybe not since the 1985.5 - '89 system has an output and a return, so should connect right up to what I have.

So, forgetting the gauges, which system would you prefer?

As for the gauges, I don't think that will be a problem as I think I can put the earlier sender on the later pump, or vice versa. I hope.

[85lebaront2]

I'm thinking the 1990+ system is the way to go because I think it would mesh best with the existing plumbing to the fuel rails. But, maybe not since the 1985.5 - '89 system has an output and a return, so should connect right up to what I have.

So, forgetting the gauges, which system would you prefer?

As for the gauges, I don't think that will be a problem as I think I can put the earlier sender on the later pump, or vice versa. I hope.

I would use the 1990+ system, but there were some changes, in 1994 I believe. Best option is see if you can find a 1990-1992/3 truck, doesn't have to be a 460 for the lines and wiring that way you won't have to fabricate everything.

Can we say ADHD? Jumping from EFI on Dad's truck to EFI on Big Blue (I though Edelbrock carburetors were your Holy Grail, and I seem to recall being somewhat raked over the coals on my decision to go to EFI on Darth.

[Gary Lewis]

I would use the 1990+ system, but there were some changes, in 1994 I believe. Best option is see if you can find a 1990-1992/3 truck, doesn't have to be a 460 for the lines and wiring that way you won't have to fabricate everything.

Can we say ADHD? Jumping from EFI on Dad's truck to EFI on Big Blue (I though Edelbrock carburetors were your Holy Grail, and I seem to recall being somewhat raked over the coals on my decision to go to EFI on Darth.

ADHD? I prefer to say that I'm advancing in parallel on several fronts.

Seriously though, if I'm learning EFI then why not do it on Big Blue as well as Dad's truck? And, I'd rather use Big Blue as the guinea pig than Dad's, especially since it'll be the easier one to do as it will be close to a bolt-on. And, what I learn on Big Blue will be directly applicable to Dad's truck.

For instance, there is the issue of the fuel system that needs to be sorted. And, it is complicated for a couple of reasons. First, the 400's & 460's didn't have EFI, so there are no bolt-on parts to buy. Second, by the time the EFI'd 460's did come along in the Bricknose era the fuel gauge senders had changed to a reversed and different resistance range - totally incompatible with Bullnose gauges.

But, fortunately, Ford did offer the 302 w/EFI in '85 & 86, and they used the same high-pressure fuel pump as the 1987 and later 460's with EFI - as shown below.

That being the case, it would seem that the most straight-forward solution would be to use the 302's fuel system, which is:

• In-tank pumps mounted on the correct 1980 - 86 sending unit so the fuel gauge works

• Reservoir/Tank Selector Valve F1TZ 9B263-B (replaced E6TZ 9B263-C a/o 9/91)

• Frame-mounted high-pressure pump E7TZ 9C407-B

So, what do y'all think? Why won't this approach work for both a 400 and a 460? (Parallel efforts. )

 

[85lebaront2]

ADHD? I prefer to say that I'm advancing in parallel on several fronts.

Seriously though, if I'm learning EFI then why not do it on Big Blue as well as Dad's truck? And, I'd rather use Big Blue as the guinea pig than Dad's, especially since it'll be the easier one to do as it will be close to a bolt-on. And, what I learn on Big Blue will be directly applicable to Dad's truck.

For instance, there is the issue of the fuel system that needs to be sorted. And, it is complicated for a couple of reasons. First, the 400's & 460's didn't have EFI, so there are no bolt-on parts to buy. Second, by the time the EFI'd 460's did come along in the Bricknose era the fuel gauge senders had changed to a reversed and different resistance range - totally incompatible with Bullnose gauges.

But, fortunately, Ford did offer the 302 w/EFI in '85 & 86, and they used the same high-pressure fuel pump as the 1987 and later 460's with EFI - as shown below.

That being the case, it would seem that the most straight-forward solution would be to use the 302's fuel system, which is:

• In-tank pumps mounted on the correct 1980 - 86 sending unit so the fuel gauge works

• Reservoir/Tank Selector Valve F1TZ 9B263-B (replaced E6TZ 9B263-C a/o 9/91)

• Frame-mounted high-pressure pump E7TZ 9C407-B

So, what do y'all think? Why won't this approach work for both a 400 and a 460? (Parallel efforts. )

Yes, and that was the point I was trying to make earlier, the 1985.5-1986 pumps and tanks will be an easier solution for you due to the fuel gauge issue. Just be sure the HP pump you get is a Bosch, most of the aftermarket replacements are junk, noisy and failure prone. I stripped a neighbors wrecked 1986 F150 and kept the HP pump, Matt ended up putting it on his truck and it was still working when he sold it. On Big Blue, I suspect the front tank is already correct due to the pressure output.

[Gary Lewis]

Yes, and that was the point I was trying to make earlier, the 1985.5-1986 pumps and tanks will be an easier solution for you due to the fuel gauge issue. Just be sure the HP pump you get is a Bosch, most of the aftermarket replacements are junk, noisy and failure prone. I stripped a neighbors wrecked 1986 F150 and kept the HP pump, Matt ended up putting it on his truck and it was still working when he sold it. On Big Blue, I suspect the front tank is already correct due to the pressure output.

Ok, I think we are on the same page. But, let me throw in two wrinkles:

• I have three brand new in-tank pumps from Vernon. Why not use those instead of some EFI-specific ones, and put them on the new sending units I also have?

• I also have a brand new 6-port selector valve from Vernon, the one those pumps are designed to switch. Why not use it instead of the EFI-specific one?

[85lebaront2]

Ok, I think we are on the same page. But, let me throw in two wrinkles:

• I have three brand new in-tank pumps from Vernon. Why not use those instead of some EFI-specific ones, and put them on the new sending units I also have?

• I also have a brand new 6-port selector valve from Vernon, the one those pumps are designed to switch. Why not use it instead of the EFI-specific one?

Gary, problem is the way the fuel system was plumbed for the 1985.5-1989 trucks. The in-tank pumps deliver fuel to the reservoir/tank selector assembly on the frame, this is where the high pressure pump picks up fuel from. Excess fuel from the tank selected is returned to that tank along with the return fuel from the engine. You can either use what Ford designed, or redesign it the way you want it. If I wanted to do away with the frame pump and reservoir, I would get a pair of Chrysler turbo or V6 pumps and install them on the 1985 pump/sender units, these are 75-80 or more psi capable pumps, then use your 6 port valve, provided it can handle the pressure, to switch tanks. The problem you will have, just as the present system does, will be starving the pumps, especially the front tank, on hard acceleration, braking and inclines when low on fuel.

Ford used the system on the early models so the high pressure pump would always have fuel, Chrysler uses a cute cup with the return acting as a jet pump to keep it full until the tank is pretty damn empty. Later Fords do the same with the pump module, it serves as a suction reservoir. FWIW, the high pressure pumps do not like being run dry.