1. Truturn makes them for with or without spinners. Check with them.

2. They are very powerful.

3. Same

4. Depends on what you want to do with the engine. You can run it anywhere from 12000 to 15000 without problems. That leaves almost any prop within reason open.

5. The additional parts cost is about $25 plus the engine.

6. Why should I, enough flyers have already done this to YS heli engines.