RE: Extreme Flight 110 Yak with DA 150
A 30x10 prop is going to be too small for a DA150, even at your altitude. So if you decide to do this and you seem like that is the way you really want to go, I would go with a 30x12 on stock mufflers or a 32x10, the 12 pitch will give you more bite, which I would think that because of where you live you need.
Also, have you given any thought to just putting pipes on the DLE. That way you could remain light. If you are at 27.5lbs now, add another maybe 8 ounces just for the 150, another 8 to 10 ounces for the extra fuel, some more weight to beef the engine box up to handle the 150, not to mention anything directly connected to the engine box and you will be pushing 30lbs on stock mufflers. At that altitude the extra weight is going to increase your stall speed because of the thin air and once the stall happens, it is not going to be subtle. It's all things you need to think about.
I'm not saying it could not be done, but please remember you are going to probably be seriously pushing the limits of the airframe itself and these are very nice flying planes. If you make it happen then power is never going to be an issue. I wish I could get my 170 stuffed into a 30 to 32lb airframe, think about the possibilities of doing multiple vertical snaps on the way uphill and just flying right through them, not having to worry about energy loss [X(], let alone having my thumbs do dumb things to me while 6 inches off the deck and knowing all I have to do is hit the rudder and power and pull out of it