I'm sure if you compare the 390 +
composite Hartzell to the 400 + Whirlwind you're going to end up close on total investment because the Hartzell composite prop is way more expensive than the WW. Does Aircraft Spruce offer a combo discount with the 400 and an WW prop that I'm not finding?
Just comparing engine prices, the A/C Spruce website (
http://www.aircraftspruce.com/catalog/eppages/superiorxp.php?clickkey=1172554) lists the IO-400 at $33889.00 and it appears that is an unassembled kit engine. The Vans special on the IO-390 at Oshkosh this year (
https://www.vansaircraft.com/pdf/Lycoming_Special_OSH2016.pdf) was $31,400 (if buying the metal Hartzell, otherwise $32,400) and that's fully assembled, preserved, and shipped. When I asked Barrett this past Oshkosh about getting a comparable fully assembled 400 delivered to my door I think they quoted me something over $38K. That's a significant price difference compared to the 390 in my book...
Maybe someone out there offers a better deal than Barrett on an assembled 400?