Mazda rotary engine. 380 installed including prop/psru
 
Another builder- That will be me in 2008!

The Plane
When selecting an airplane kit, I was of course enamoured with the fast-glass Lancair's & Velocity's.

Being an engineer, I drew up a list of objective, real-world requirements, and discovered that not many planes really qualified.

4-seats, good payload, comfortable cockpit (I'm 6'3"), "affordable" to buy, and "affordable" to insure and maintain. The "affordability" requirement eliminated those fast-movers ;/)

The Zenith CH801 showed up on my radar just due to the number of seats, payload, and price. But it also has good range, a variety of engine options, and the STOL capability is a great benefit for hunting/camping... The 801 just kept coming back to me as a good fit; finally I took the plunge & ordered the empennage.

I intend to use it primarily as a day, VFR plane. I'll put lights on it in case I ever "need" to do some night flying, but that's not the intent. I want something I can run back & forth to the deer lease in; visit Colorado & the Ozarks w/o the long drive & traffic; and just go flightseeing.

If you're not aware, Abacus has a very nicely done model of the 801 available for MS Flight Sim. It was done with direct cooperation of an 801 builder & pilot, and is said to be as realistic as you can get. It's less than $20, google it.

Engine-
I was evaluating the 4.3 liter chevy vortec v6 for quite some time, here are some useful links:
http://www.beltedair.com
http://www.sdsefi.com

Although I think that motor is a very workable and affordable option, I decided against it due to the weight penalty. Initially I was unaware of any autoconversion option that didn't come with a weight gain, but then I stumbled onto the Mazda rotary conversion.

http://rotaryaviation.com has information & products for converting Mazda RX7/8 rotaries to airplane applications, and get this- The installed weight is within 20lbs of certified airplane engines! Even with water cooling, their power to weight ratio is that high. Another advantage to rotaries is they have significantly fewer moving parts- no valves, camshafts, pistons moving back & forth, etc. Just a rotor & some pumps.

I took the plunge and ordered a salvage RX-8 engine, and placed my orders for the PSRU & dual ECU from rotary aviation. This system should give me 200hp at the same weight & better reliability than a io360. Projected cost is $8K installed.

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I won't get into the autoconversion / STC religious war here, other than to say it usually comes down to reliability / credibility. With the current crankshaft / cylinder head AD's, you'd be a fool to believe STC'd engines have either. Might as well save money and go with a company that makes over 2,000,000 engines/year, and actually supports them.

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