Joe,
The YS engines tend to need higher nitro than the OS 2-strokes and I don't think the fuel economy is better. In fact I'm pretty sure the YS will use more. Dude, keep it simple. Put an OS 120Ax in that Venus 2 and fly. You're not going to be in Masters for at least another year. LOL

If you're having a hard time buying fuel, talk to the guys at the Jackson contest. We usually do a mass fuel purchase from S+W. I don't want to disclose the price here but it's A LOT less than what you're paying.

I'll bring a Venus 2 with an OS 120Ax to Jackson so that you can fly it. Trust me - it's all you need for now.

John Pavlick
Team Black Magic