RE: Engine Starter
You will need a gear reduction starter to start that YS. A 4S lipo is a great idea as well. I know of 3 starters available: Magnum is a simple 2 gear system with medium quality. The Kavan starter uses a planetary gear and is better quality (German I think). These 2 are the most popular around here. The last is a Turnigy belt drive starter sold by Hobby King. I've never seen one though but I'm sure it would work fine. It's the cheapest.
Hope that helps.
Keven