Printing up some gauge pods for the truck. I had bought a generic A Pillar pod cluster but the angle isn’t right for the square body. Printing in PETG-CF.
Here’s the design I’m using. Should work great for the Glowshift water temp gauge for the hopper and the UEGO gauge for the AFR.
I’m just going to use some double sided tape or maybe some velcro tape and smack them on the top of the dash. Velcro seems like a nice idea, I can just lay down a long strip and configure it as I want.
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Tested two things today on the truck.
The TPU printed gasket/insulating spacer and a little Holley 94 carburetor.
I noticed the barrels are about as big as the front barrels on a Quadrajet. I bought a cheapo clone carburetor of a Holley 94 and made sure the float was set correctly. With a fuel pressure regulator set as low as possible this carburetor runs the engine fairly well at just 1.5-2 PSI of pressure.
I haven’t set the throttle cable up yet. One notable thing is the accelerator pump is awfully small and just barely covers the throttle opening suddenly. With proper jetting that should be okay.
Now for the hard part of making an upper plenum that will fit this Holley in the back and my 3" throttle body for woodgas. I originally was going to try a flange shaped exactly for the Quadrajet or a 2x6 steel tube but I’ve since put an adapter that uses a square bore flange. That way I won’t have any internal bolts that I’ll have to worry about or any crazy flow characteristics.
I should have a few more inches of clearance with this stock hood, if I absolutely have to I’ll either cut a relief or break down and get a Grump Hump hood.
Here’s the idea so far for the Woodgas side of things if I can make it work:
central Tree should be in the 3-3.5" range, it’ll match the TB. Air is introduced from the front, but the source of air will be near the fender to get cooler air. I’ll be putting in two 2" pvc lines for woodgas. I’m bringing them in through the fenders on either side, sort of future proofing if I decide to put in headers I know space will be limited.
One nice thing about the Square Body trucks is the fenders scallop in the upper part so the pipes won’t actually be proud of the fenders if I do it right.
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Just because I use a little Computer Aided Design doesn’t mean I won’t go straight to the other CAD, Cardboard Aided Design. I’m a touch and see experience kind of learner.
In order for the throttle lever to swing I know I need to have the carb sticking up at least 1 inch. Looking at the cast adapter I also had to kick the carb back.
Now to look back at my carburetor and figure out if I can slice cut a 3" pipe and have it clear the float bowl.
Edit:
With this mocked up I can weld in a pipe on the face of that front spot.
Better news is I can still fit my tea strainer emergency filter in the event a heavy piece of soot or char somehow gets sucked up to the throttle.
I’m gonna take the Holley back off of the truck and set this on just to double check my clearances.
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By the skin of my teeth I can make it. I can take up more space with a thicker gasket if need be. I just didn’t want any sharp bends that limited my flow, this should offer the Woodgas a straight shot to the intake. It’s a dual plane intake so I didn’t want to put my woodgas on one side and have it favor that side in flow.
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The bottom flange is going to be 1/4" plate, and I think to help keep it from warping I’m going to save cutting out the center until all the welding is done. Rest of this is going to be 1/8" plate.
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I vaguely remember buying this throttle body on eBay, it’s a ~3" sized one I think they’re for LS swaps. The plate it came with was already tapped for threads so I figured I’d just insert a pipe. Unfortunately it’s aluminum so I’ll either silver solder or JB Weld epoxy this to seal it.
Those with a trained eye might notice the pipe I got to fit was a 3" exhaust pipe coupler. The OD is about 3.17" and I had to sand it down a little but it’s a press or hammer tight fit. Mechanically it’s solid it just isn’t airtight at the moment.
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Done, for now. It’s 10pm so I’m going to let this cool off and get some lotion on my welder’s burn.
This Vevor welder I got makes really raised beads. All those nice flat beads are actually me filling huge gaps.
Almost forgot I need to add my hose barbs for vacuum advance, PCV and EGR.
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When welding thick metal I have noticed my weld were raised up like that too. After watching some YouTube videos I tried changing my technique. Now I’m zigzagging over the joint and that has helped a lot to flatten those welds. Using the same technique makes welding with gaps really easy too.
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I must be zigzagging too tight, I’m used to staying really small on the weld pool because of my flux core welder. It makes sense to spread it out more, though.
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Quarter inch and over chamfer the edges and run a root pass. Clean it really well and then you can run a fairly flat fillet weld. Under a quarter, just leave about a sixteenth gap for full penetration.
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Oops
Forgot to factor in the water neck.
Now the real question: shorten it or elongate the tube?
I’ll just shorten it. If that doesn’t work I’ll try to flange the face for the throttle body or move to a smaller TB.
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Much better.
I expected this but I do have some air leaks. Wondering now if I should just use sealant on all the joints or carefully grind and reweld everything.
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Or you could just add some solder. I did that on an older Kohler 14hp metal gas tank and it worked great.
GC
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I like that idea. I ordered some of those Bernzomatic rods. Hopefully those will work. I was considering JB Weld because it’s worked for me before using on the outside of the intake but it’s such a mess.
Wish someone made a spray on sealant that could handle engine temps and be gasoline resistant.
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You can spray sodium silicate, which is the head gasket sealer stuff. It hardens with CO2 exposure. It is also used to seal concrete floors, where you spray it on. 
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Little side tangent. My kludge repair on the exhaust manifold studs didn’t last. I’ve dropped two studs so far. Ordered some replacement stock manifolds from Rock Auto. If I’m going to run an AFR meter I can’t have exhaust leaks at the dang Y Pipe so that was a necessary repair.
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Manifolds were supposed to arrive today. Came home to see the box damaged and only my driver’s side manifold in the box. Looks torn on one end. C’mon Rock Auto why are you putting cast iron in a single corrugated box?
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One weird thing about these new manifolds is there’s an 1/8" NPT plug at every exhaust port and it has an O2 bung at the exit. Too bad I can’t/shouldn’t put the Wideband there, I think that would cook the sensor.
I’m assuming the smaller plugs are for air injection type stuff for Smog?
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Yep, I remember those. We called them afterburner ports. Rob power from the motor to pump air into those things to supposedly lower emissions.
GC
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Luckily this truck doesn’t have a smog pump.
Oddly enough I have what remains of the original exhaust and there wasn’t a catalytic converter either. Just a resonator and two mufflers in line. Maybe they chopped out the old cat and put the resonator in.
Only emissions stuff I can see this engine having is the EGR, which means my intake and heads are more restrictive apparently but that’s only compared to Edelbrock or Weiand stuff I bet.
I’d like to eventually figure out a head swap that bumps the compression a little. Maybe to a modern but conservative 11:1 ratio if that can even be figured out just by head swaps. Truck runs fine how it is right now so I’m not going to poke the bear and go changing perfectly good stuff.
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