A litle more power

[avidflyer]

I had a ride in a Kitfox 4 XL with a 503 a couple of weeks ago. I was really surprised at how well it performed with only 52 HP. We flew out of Pensecola Fl so we were nearly at sea level to start with and it was about 50 F. Airplane weighed 525 empty. That tells a lot. Build your plane as light as possible, the 582 will give a lot of power, especially when you are flying solo. It seems the 670 is a bit less proven out at this point, overheating and exhaust issues in some of them. I would suggest sticking with the 582 until or unless you can go to the 912. One thing I would suggest as well, is if your fuselage isn't covered yet, widen the fuselage before you cover it. An extra 4" in width will make a world of difference. On my Avid MK IV, I used 7' of tubing on each side so weight increase is very small . Jim Chuk

[Dusty]

grdev
The engine you choose to use depends on your "mission"
Local flying with the occasional cross country then the 582 will be perfect
If flying with other faster aircraft a 912 would be better.
The 670 would be a good compromise.
Other than the exhaust ,it will be a straight replacement for the 582 and parts are easy to obtain and won't require a mortgage