Lube? They use some 30 wt in the crankcase.

I ran it yesterday, it kept going lean....got POed. It only ran with the choke on.

Did some research. Bent up the pop off lever about 0.01". Opened up the main jet a little using a half reamer made out of a sewing needle. I can't say exactly how much though, perhaps a few thousands. I suspect the pop off lever did most of the good. It now runs properly without an air cleaner! It still rubs me the wrong way not not have ajustment screws. Anyway with a Bambula 22 x 8 it idles reliably and crazy slow. Below 1200 something starts to click in the engine. It spins up to 5500 with no hesitation. It seems to run in the mid 5K range with most every reasonable prop. A Mens 24x10 does bring it down to 4900. A 20x8 only spins up a little faster than the 22x8. For yucks I tried a 16x8, only 7500. Removing the muffler gained about 500 RPM. I opened up the exit holes and tossed the screen and got back 300. It is not loud without the muffler. If I actually fly it I will probably make a header.

What about the long intake manifold? I'd like to make a short one. This engine gets the pulse for the carb from the intake manifold. Do I need the long intake plenum to make the pulse work? Or, is it simply the engine sucking in the charge that makes the pulse? I guess I could make a long plenum by installing the carb on the firewall, or behind it, and use a bit of rubber hose to connect it to an intake manfild stub tha bolts to the engine.