I forget what kind of wood you use, is it mostly softwoods?
I guess Imbert design plus heavy truck and larger V8 equals a little less efficiency.
Then again let’s be honest the Square Body trucks and the TH400 we’re lucky to get double digit liquid fuel economy.
Not at all, a properly tuned quadrajet will get excellent fuel economy. For being a full size V8 truck. I had a 73 standard cab long bed dually 4wd 350 4 speed that if driven modesty and kept out of the secondarys could get 21mpg. Around town 18. Make no mistake a heavy foot would put it in the single digits, but not uncommon at all to get 14-16Mpg with a Carter afb on it. My 84 Cheyenne 350/th350 averaged 14Mpg, my 86 suburban 350/700r4 4wd on 33" tires with stock gears consistently got 13mpg
It’ll be interesting to see how good my MPG is now that I’ve divorced the barrels on the spare QJet. No way to accidentally crack the whip on the monster secondaries.
You will be like the guy that has a lawnmower carburetor on his truck trying to get 40 mpg. But it will more like two on your truck. So maybe just under 20 mpg?
It will probably go down. divorces are usually costly and drain people of energy.
Today was very fun reading, both Niklas and Göran, thank you Marcus and Göran, you made my day.
Thanks for the Mudsummer report, Göran. I had to replace milk and sugar with lemon juice in my coffee 
Something I have never wondered about before. How four rear tires might effect mileage.
Ha! That I can answer TomH.
65+ psi in stiff sides walls, narrow aspect ratio tires have very low rolling resistances. It is just that usually this “cheat” is installed onto big air pushing bodyworks.
Roll along at 45-55 mph is another very effective fuel use “cheat”.
The higher GVW vehicles did not have the power/milages killing emissions added systems layered-on.
Relative loose worn engine internals is a big factor too. Shhh. Up the thermostat to burn as fuel the oil consumed. De-blade that that power sucking fan adds even more fuel used saved. Those older AC systems are fuel milage killers too. Out with it.
But honestly it is startling to experience first hand just how effective those evolved GM-Rochester tiny primary bores Quadjets really are capable of when set up for best fuel-usage, and you restrain yourself to feather-foot driving. Drive by an intake manifold vacuum gauge. Not your ass or speedo.
S.U.
Oh yeah those pizza cutter tires will aid in fuel economy. Same if you get a more hard rubber tire. My dad never liked Michelins because of how sticky they are compared to others.
Well this chevy is a wood guzzler, eats 4 times as much wood as my volvo did, but its heavy, 3times as big engine, rear is geared very slow. The two barrel carb is somewhat effective, but it really drinks gas, 2liters/10km.
I try to use as much hardwood i get, but for now it’s only softer woods, and inferior, old, rotten, mushy wood, 90% “leaf-tree” woods though.
By the way, today i ran out of the wet, bad wood residues in the hopper, starting to consume what i put in it yesterday, real difference, runs rich almost all the time, “blubbers” in the exhaust, cant compensate with my air valve enough, have to re-adjust the second air valve that is controlled from the gas throttle 
thanks for the nice video , nice swedish landscape…
Some more pic’s from today.
My daily driver, my little VW rabbit/caddy, has to retire, just remembered the other day it run out of inspection period, and there is to much to fix, rust, exhaust leaking up front and the rear muffler is missing, gearbox needs to be replaced, fifth gear long gone, and some more small stuff. So the last days have been running 100% on wood.
Next thing i need to dig deeper in the hard shifting phenomena, as for now i manage well with let of the accelerator, just when i “get the feeling” it’s about to shift up.
Goran it actually isn’t bad for the transmission to shift harder than normal. Automatics are basically slipping the clutch into each gear, and softer shifting equals faster wearing of the clutches.
I still think it’s grabbing harder due to weaker manifold vacuum, the modulator thinks you’re in the high RPM wide open throttle and must shift hard to not damage the clutches. When in reality your throttle is open more to compensate for fuel flow, so RPM is not that high and is unwarranted.
Still not fun for the wife or dog I’m sure.
I am sure I’ll be experiencing the same issues in my truck soon. Maybe some sort of tachometer controlled vacuum solenoid would be a good idea? No need to switch settings when changing fuels.
You’re right Cody, hard shifting is’nt very bad for the transmission, (maybe for the prop-shaft joints, whatever they called in english), much worse is slip-shifting, run-up, i remember when i worked on heavy trucks and busses, them big automatic transmissions i used a special tool (stoneage-computer) to measure the time shifting in milliseconds, it was very little needed for the rpm’s to raise (slipping).
It is’nt much of a priority to fix on the chevy, just irritating when shifting takes place smooth as firing a shotgun.
First thing im gonna do is fix a tachometer that works with HEI ignition, seems no one knows in Europe what to use?
Then im gonna drive with a vacuummeter on trans vacuum line, and compare results woodgas/gasoline, i believe it was you Cody that suggested that? Or SteveU?
Anyhow i still got the vacuum modulator from the diesel engine (somewhere) that i believe could be used, it’s got a mechanical connection to the throttle.
They are called universal joints or just U-joints in English, Goran. They go on the drive shaft. I think the Brits call them prop shafts as well. 
I been thinking about rebuilding my condensate tank for a while now, at first i had a container under the truck, with a tap i could maneuver from the side, that one got clogged often so i replaced it with a cheap, replaceable plastic can, recessed in the bed, i was never satisfied with this, sloppy job carry it away and empty.
And sometimes (when i forgot to empty it regularly) hopper juice was standing all the way up in the hose- splash! when disconnecting the hose from the can.
Then i learned Waynes clever solution, to let the tar stay in the bottom
The other week i got inspired by JO:s nice hopper juice container build
stainless shouldn’t have a problem which I think is all they have in sweden unless it is imported. 
If it is a cheap spring like we have in the states, made to look like stainless, it is zinc coated, so the acid will probably eat away at the zinc pretty quickly, and maybe through the metal eventually. I would probably put the spring where it doesn’t have to sit in the juice so it has a chance to dry off. BUT if you are really worried about it, you can plastic coat it especially if you have a bunch of say packing peanuts from prime day deals.
