Here are the test results and observations for the AP Wasp with the Geezer modified R/C carb.

1. These results and observations are based on testing only one example of the AP Wasp and may not apply to other or all Wasps.
2. All tests were done using a 6x3 Master Airscrew prop and a 1 oz. plastic clunk tank modified to operate as a uniflow. Test set-up is shown in the attached photo. Altitude at test sight is 1600 ft. above sea level.
3. The engine was checked for crankshaft drag and was found to have a good running fit.
4. The engine was run at a 4 cycle and then a rich 2 cycle for the recommended 40 minutes using 5% nitro and 28% all castor fuel but still would not hold a fast 2 cycle needle setting. More running would be needed.
5. An additional 15 minutes of running was done using 15% nitro and 20 % all castor fuel. With the stock carb. bore of 3 mm (.118") the best the engine would do was 14.7K rpm.
6. The carb. was then bored out to 3.45 mm (.136"), an area increase of 53% and test #5 repeated. The engine would now do 15.5K rpm.
7. The fuel was changed to 35% nitro and 20% oil (1/2 castor). The engine would now hold a high speed 2 cycle needle at 16.6K rpm.

Observations:
1. my engine was a bear to hand start particularly on low nitro fuels. It was very sensitive to flooding and never seemed to give an indication as to when it was ready to run. You would be flipping away and then all of a sudden it would take off. Finding the exact needed mixture to start proved a delicate task. Of course, using an electric starter would ease this problem.
2. I found the stock muffler to be ineffective, with engine noise still loud.
3. My sample ran very smoothly with low vibration using a balanced prop.
4. The engine seemed to like the uniflow tank with very little change in rpm during the run.
5. The long taper on the needle valve made for broad adjustments, a good feature.

Conclusions:
Again, based on only one engine tested.
1. After I did the 35% nitro test, I thought I would see what my old well used Cox TD .049 would do on the same prop/ fuel/ tank combo. To my surprise, it humped away at 15.5K rpm! It also started after just a couple of flips every time.
2. I thought the Wasp with a displacement 24% larger would do much better than the TD... not so in this case. The Wasp weighs 56.4 grams with muffler and 52 grams without, the TD weighs 47.6 grams. The TD doesn't need almost an hour of running to break in either.
3. I prefer the TD .049 but since this engine is no longer manufactured, the Wasp is a suitable substitute... how long it will last is still unknown.
4. I think the carb. can still be bored out to 4mm (.157") but this will have to wait until next spring.

Orv.

Norvel and Wasp engines run best when allowed to rev.  When I first started using them, I would prop with a 6x3, just as if running a TD.  They would invariably overheat half way through a stunt flight.  Now I run 10% Nitro and APC 5.5x2.5 or 6x2 props.  Ground rpm around 19,000.  Perfect runs through the whole pattern on 45 to 48 ft. lines.

Electric starter!  I don't recall having ever tried to start a Wasp by hand. I suppose I should give it a shot sometime.  Then again .....

Oddly enough, the TD and Medallion engines are much harder to start with an electric starter than they are by hand.  Go figure!