If the tank was too high, it should have affected any engine equally. The carb on a 2stroke is about 1" above the centerline of the crankshaft. The carb on that (and most) 4stroke is about 1" above the centerline of the crankshaft. The carbs on the two engines wound up in exactly the same relationship to the tank in the airplane, so if the tank had been too high for one engine it would have been too high for the other, pure and simple. And the fuel tubing was routed roughly the same. The tank was in the same place in the airplane for the 2cycle it was for the 4cycle.

The 4cycle flooded for a number of reasons that were combined. The 2cycle didn't flood for another set of reasons. None of the reasons for either engine included the tank being too high.... or low.... or too far back.

That 4cycle flooded probably because of a number of reasons. All of them are worth listing for the guy who asked if there were differences he should consider for 4strokes. That engine was not broken in yet. It's high speed was very sensitive and the lowspeed wasn't properly set. I was not using whatever choking technique the engine might or might not have liked. The design of the "downdraft pipe" compounded the problem greatly. The downdraft pipe is a unique feature of most 4strokes. When it's upside down it sets up conditions worth considering and worth understanding.