A 3" on a stock 302 is mostly closed but I can still adjust to either side good. I didn’t want to choke it down on gasoline though.
Marvin
Nope, a 2" will likely be 1/2 to 3/4 open… Just a wild guess based on mine, 318 and a 1 7/8" opening, the only time I had the valve fully open is when fuel got rich at the end of the hopper or Making tar because of to fine a fuel.
Hello Mr. Pete ,
I think a rule of thumbs if you are just using the air to mix with wood gas, piping about half the size of the wood gas plumbing would be OK . The amount you will have to close or open the valve will depend on how tight your system is and how tight the char is in the gasifier.
When running on gasoline I draw the combustion air through the mixing chamber so I have piping the same size as the gas lines . I have two 2 inch for wood gas and also two 2 inch for the mixing air. When running on woodgas I will usually have both air mix valves about ¼ to ⅜ open . I find by using two smaller lines and valves vs one large pipe and valve I can fine tune easily .
Wayne, Terry & Marvin, Thanks for the input.
Since most all my gasoline driveing is at low speeds, start up and shut down, I find myself leaving the air valves set at one place and just tweek one a little to adjust for woodgas. One is 2" and one is 1-1/4"
Thanks Carl, I happened to find 2 VW 17/8 throttle bodies.
With some machining to get rid of the electric motor & gear box, these seem to be very well made units. Will make a manifold on the intake tube & attach air cleaners directly to the throttle bodies with no extension tubing.
Have the wood gas throttle & 700r4 TV cable working. Throttle & cable both adjustable.
“With some machining to get rid of the electric motor & gear box, these seem to be very well made units.” Peter, you amaze me!! How do you find these gems, and two at a time?? They are diamonds in the rough, and you bring out their re-purposed qualities. I salute you my friend.
Edit: What year VW? Oh, why do I even ask, I don’t think they have VW’s in Arkansas! 
Peter,
Nice looking work there,
slap it on the mill and take off the stuff ya dont need, luv it.
I hope to do the same when I get that far. I wish I could look at a catalog that had all the throttle bodies ever made so I could pick the one that would work the best.
Thanks Carl & Wes,
No idea what year ---- know it is VW by the stamping on the unit.
Yes, a throttle body catalog would be very handy ------ save many hours of searching!!
Hey Wes selection is easy - use what is readily available salvage with the closest bore size.
Currenty here Chrysler/Dodge/Plymouth mini-vans get the nod for air control valves. Nother place it might be Honda or Suburu. It’s all good man.
Regards
Steve Unruh
Steve,
The reason I chose those particular throttle bodies is the very graduated ramping under the butterflies. Typical for Germans to take a working piece & make it a little better just because they can!! This is a work ethic that actually existed in this country at one time.
Peter, I can hear it running already … Last time Wayne and I did time trials I seem to recall it was zero to 60 in around 35 seconds with old blue. I think old blue moved to Florida. Too bad that friggin tornado wiped out that beautiful valley where we were playing and killed all those folks. The dafodils were pretty that March … ML
Been chunking all different forms of fuel. This is 1x3 strapping ----- about 10 — 12 minutes.
Have chunked round & square hard & soft wood up to 3 inches ------ dry & green does not seem to make any difference. Found construction lumber makes much less of a mess than trees. Also found that a dull blade shatters the wood better than sharp. When I sharpened the blade it looked like a saw cut ---- don’t know which burns better in a gasser.
Drooling Peter. Just drooling.
Better than having your own oil well Peter!
That is pretty damned awesome!
I’ve heard that a sharp cutting action is better than a dull crunching action for various reasons.
Chris, you can drool ------ just don’t get the wood wet!!
Don, that is the truth.
Brian, What would those various reasons be? Seems the puffed up wood may dry & burn better. Sharp or dull ----- no difference to the lathe cutting through.
The ones I can remember off the top of my head being: 1. Dull-cutting wood crushes all the wood capilaries closed so it can’t “breath” and exchange gases as easy; 2. Splintering wood changes the surface area-to-volume ratio by 100-fold which throws off the balance of where the gases get formed/exchanged; 3. Splintered wood cooks down to a fine choking dust instead of nice solid chunks of charcoal with good gas exchange/flow.
I’m going off collected second-hand knowledge so hopefully someone with first-hand knowledge can confirm or correct my findings, as needed.
Thanks Brian, maybe Wayne can take a look at my pile and chime in on this one.