Yea I'll definately need mixture control. I'll have to automate it. And I was thinking of a method for compression too. There are small motorcycle turbos that operate on electric motors. I know they don't do much for big capacity engines but for a small 100cc engine they'll do heaps at high altitude. Or even making an inlet compression duct. I've calculated this thing to reach pretty high velocities so that might be an option too.

The 3W 100 seems to be going for about a grand which is a little high for my engine budget. But I must say the specs are very attractive. Any other ideas? If you guys are interested I'll put up engineering drawings and CFD simulations up from the wings so far.