Greg and Martin,

Sounds like we're all pretty much agreed. I just rambled on about the internal processes. You BOTHidentified the practical side - that converted glow engines' throttles match the rich mix tolerance of methanol glow fuel better than the more finicky mixture tolerance of kerosene-based diesel fuels. Whether it means no gain from throttle above 2/3 or 3/4 - which I've also observed - or it suggests it may be a good idea to replace the stock OEM carb with one for a smalller engine.

How much smaller? Hmmm. Perhaps the torque performance increase we see with our diesels would indicate that. If a .25 diesel can turn a larger prop the same RPMas a .36 or .40, would that suggest a better fit for diesel-converted .36 to .40 engines to use a .25-size carb? This example would match the favorable torque around torque peak RPMfrom the more potent kerosene heat-yield. Remember - torque peak RPMfor any engine is very likely to be where the volumetric efficiency is best. ...Where the engine can take-in and exhaust fuel-air mixture most efficiently.

Both the ENYA restricted carb, and Bob D's suggestion of a 'NASCAR-plate' type restrictor seem to address this.

Whatever, diesels are very gratifying to run. I thank any and all who keep it possible for us to get and use them!