The Master Airscrew was only mounted for display purposes. I had an APC prop in mind, but I'll consider using the Graupner speed prop. Thanks for the tip! I've good experiences with the plastic click-on spinners from Carl Goldberg, unless we're exceeding the rpm-limit. I know. Maybe I'll mount an aluminum spinner eventually, but with the stock engine it's no problem. I've ordered two TruTurn 1-3/4" spinners for the Stiletto's though.

I spoke a Line-Control speed race enthusiast last time and he's using the same MVVS as I do. He'd manage to tune it with a easy solution in my opinion. Using a shimmy of 0,5mm under the edge of the cylinder, the timing is adjusted to 162°. The new timing should already be a big improvement. To keep the compression the same you need to remove the 0,5mm from the top of the cylinder head. That's a job I could do with ease at school. In combination with a APC 6,5x6,5 and 6mm venturi (like you advised also) it was quite an improvement. I'll check the internet for a MACS 1110, I'm curious about the possibilities.