Hi, I’m new here and I’ve been pouring over the posts and reading Wayne’s book. I’m shopping for a donor truck and I really like the older Fords. I understand the recommendation by Wayne to go with a MPFI engine but I’m wondering if we could have a pros and cons conversation about the two options. I am currently looking at a 94 F-150 with a multi-port fuel injected 460 as well as a 79 F-150 with a carbuerated 460. Any and all input is appreciated. Thanks.
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As someone who has operated both just like Wayne has, the fuel injection is very handy.
You can shut it off with a switch, or use a PWM or Rheostat to turn down the fuel pump voltage to a trickle.
With my old Mazda carbureted with a Weber 32/36 I had a hard time switching over. I used a cutoff solenoid to let the float bowl empty out, but the main issue was setting the air fuel ratio just right to keep it going after the gasoline was depleted. And it would take longer for the fuel to get used up so it was a guestimation every time. Typically I’d just wait for the gasoline to get used up, then try to set the air just in time, or crank the engine back up on the woodgas. Didn’t help I was entirely new to woodgas.
With my Sierra in the handful of times I’ve experimented with it, I could wait for the gasifier to be warmed up, shut off my fuel pump and still have it running decent. The computer sort of bridged the gap when it got really rich from incoming woodgas.
There’s also the potential to really mess up your carburetor. Marcus Norman has a video of his truck’s carburetor and it’s just absolutely sooted up. It’s amazing he gets an idle on gasoline to be honest.
The gas is filtered, but soot will re form in the throttle body and intake area especially if you run softwoods and sappy resinous woods like Pine.
You can always make a custom intake so you have a woodgas throttle and a carburetor separately. I have plans to do that with my 76 Sierra. Just need to test how small of a carb I can use to save space. Trying a Harley Sportster CV style carb in the near future.
MPFI will let you burn off the soot with a torch while the engine is running on gasoline, but there’s multiple ways to skin that cat. Mike LaRosa(RIP)'s method was to use boiling hot water and slowly trickle it down the throttle body after the engine was warmed up. He had to do this because some newer GM vehicles have plastic intake plenums.
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Hello Andy and welcome to the DOW
I would try to avoid the carb and go with the fuel injection .
This is a 460 but has a carb. If I had to choose I would go fuel injected
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Welcome Andy. If you believe that somehow you are going to be able to get replacement electronics for the 94 then that would be the best choice. Lose that ECM and you are “attached to another object by an inclined plane wrapped helically around an axis.” The definition of being screwed. The 79 would be the preppers choice and though I’m not a wood gas driver I believe that a throttle body tapped into a 3 inch spacer beneath the carb would solve the caked soot issue as seen in the Marcus carb and an on/off solenoid could allow a regular gas fed carb to be used when needed. At least theoretically. Another option and in my opinion, a better one, would be to forgo gasoline and rig for propane as an alternate fuel to work with wood gas… Of course It should be acknowledged that I see a bad moon rising.
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Welcome, I have d.o.w. two Fords, 93-5.8, and a 98 2.5. Both are fuel inj., much easier to install, and drive
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That boiling water trick didnt work for me at all. I tryed also acetone and alcohol but nothing worked. Stay away from plastic manifolds or even better, burn sootless gas.
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Dad has comented before about his ford. Saying it was always tricky getting the fuel to air ratio right as carb runs itself dry. Basically same thing Cody discribs above.
He would be way too rich if wood gas was opend while carb still had residual fuel.
Marcus has said before it was always easier for him(at least in the begining) to roll over onto wood gas as he was going down the road, that way he had the kinetic energy of the truck to give him time to set the air.
Speaking of which, dad was dropping off some scrap the other day and asked one the the guys if he could get a fuel injector to play with. For the same reasons we were just speaking about.
The guy said I’ve got just what you need and grabed a fuel injected TB of the shelf. Well…it wasnt really what dad had in mind but he took it to mess around with anyway.
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sure looks like a tbi off a 90’s gmt400 chevy to me
yes in the toyota i would let it run wildly rich with the woodgas open while the carb is running out the engine would buck and chug running rich for about 10-30 seconds but once i knew where my air mix wanted to be it was very easy to drive it that way. only real downside is my system passes a lot of soot and will clog up the carb about every 2500-3000 miles and need a good cleaning. i dont think i would run through the carb if i did it over again unless it was a woodgas only motor or had a very well performing filter system to prevent the sooting issues. But the toyota only uses gasoline to warm up and is immediately switched over to woodgas, so it is not a huge deal to me really. But i sure do like the ability in my dodge to switch back to gasoline on the fly and not have it run poorly from soot contamination
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Hi Tom, thanks for your input. That helically wrapped inclined plane thing sounds painful so yeah, I would want to avoid that. But on a serious note, you touched on a very important issue and that is the prepper thing. I’m wanting a wood gas truck for all the advantages it has to offer in our present reality but I’m also wanting a solid solution for a SHTF situation. Maybe I can’t have both in one truck but that’s what I’m trying to figure out. If the ECM is the only weak link in the MPFI system then I would plan to have a few extras on the shelf. On the carbureted engine your suggestion of a throttle body and spacer under the carb sounds like a reasonable and easy enough solution. Does anyone have any thoughts or experience with that method?
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Hello Andy
Several years back I drove a 87 dodge and a 84 ford that I had a spacer under the carb and could run gasoline or wood gas or a mix of ether . Gets real complicated with two throttle pedals .
I ended up taking the spacer out and running the wood gas through the carb .
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Hi Andy, i drive carburetted, with a spacer/Y pipe under carb, mostly because there is’nt much fuel injected v8’s available in Sweden.
In my thread “Woodrunner chevy” there is some about it, and some drawings around posts 35-53 some. This one i use one pedal, and a “throttle shifter”
Works very well, but makes it harder to “hybrid” and is pretty difficult to build. If i was to build something like it i would probably search a enormous (3-4") 3-way ball valve to shift fuel, and let mixer and carb open simultaneously all the time (needs to stop fuel to carb, otherway the acc-pump will fill the intake)
Otherwise i would retrofit a fuel injection system, those new “electro-carbs” or a old working system ripped out of another car.
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It’s good to know that some one has done the spacer in a real world application Wayne. In theory I had assumed that it would be operated with a push/pull cable but the proof is in the pudding. As far as I know, ECM’s are not interchangeable Andy. I think Marcus mentioned it as well. However the MPFI is not the only thing controlled by it. I don’t know about 90’s Fords so if they are still using a regular gear driven distributor that’s a plus and some of the other sensors can be worked around. If you have fat pockets you could buy both trucks and if the tech version defaults then just swap the gasifier over to the other.
Goran got in ahead of me with more actual use information. Very interesting. Always something that can only be learned by actual doing.
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Just so you all know fuel injection module “brains” can be swapped interchanged with-in same manufacturers type age era’s. Up through 1996 for sure. Even into the early 2000’s until the introduction to CAN buss. From then on each controller module in the system has a broadcasting out system registered serial number that must be recognized by the vehicle other modules as valid.
This is not speculation. Working in dealership shop in the 1990’s it was common to have a cabinet of take-out control modules; or modules marked with one know problem and do as FORD in their training said, “Swap With A Known Good Part As A Diagnostic”. I and others did do this in the Chrysler/Plymouth/Jeep shop.
Was NOT approved to rob an ECM out of a good running vehicle just to test with!! A problem in the downed vehicle could kill it too! Like popping fuse after fuse searching for a problem.
My 1994 Ford F-150’s ECM has a died airflow meter calculation section. It still does work in a fall-back Speed-Density mode. I have a wrecking yard take out module that someday ambitious enough to remover the left front inner wheel splash guard I’ll get around to swapping in.
The programming of the module must match vehicle equipment. V-8 for V-8. Same type of six cylinder to same type of six cylinder. Transmissions usually must be matching. Emissions installed equipment on these earlies usually not so important. So what it codes out it cannot get response form an AIR system not present.
The later Controller Area Network systems most of the individual vehicle sensor are changed over to analog-to-digital out self-processor types. Makes for direct into the data bus stream contributions. Greatly simplified the overall wiring not having to directly send analog individually wired to one of the main processors for conversion to digital.
These sensor cost much more. Are more heat sensitive. And die much easier than the earlier straight analog ones.
Seriously; invest in one of the newer handheld code scanners. Just see how many modules it can ID a vehicle having. The fewer the better. My 1994 Ford F-150 has two. My sisters 2017 Ford F-150 had 53 electronic controller modules. My Wife’s 2014 Ford Edge has 12.
Same-same. Old vehicles you want the most factory least option version you can find. Less to go wrong. Less failures cards to have to account for affecting each other adversely.
Walk away from a highly optioned old one; even if it is free. Free is a disease easily caught. Hard to shake loose of. Hard to cure.
Steve unruh
Ha! Ha! And my selected 2017 GMC cutaway box van only has two Electronic control modals. Wind up windows. Vacuum controlled HVAC control mode actuators. SEE!! It is possible to still go simple. S.U.
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