Photos of my H2AD
Here is a link to some photos of my H2AD installation, including Van's tricycle H2AD engine mount and my modifications to Van's carb linkage mount.
http://www.eaa582.org/gallery/thumbnails.php?album=19&page=8
In the different pages in that photogallery you can also see how I ran the fuel lines to the front mounted mechanical fuel pump and modified my top cowl for clearance. I'd install a mechanical pump and stay away from dual electric pumps, you have to modify the cowl anyway.
And you can see how I built the baffles and mounted the oil cooler behind #3 cylinder. Temps are all in the "normal" range with this configuration (EIS-4000 4 cyl monitoring) and I don't think I'd change anything if I was to use this engine in the next RV I build.
After flying my T'bird 250 hours it's first year, and now that it's getting cold outside, I'm starting to miss having a project in the garage.
My engine doesn't have the much sought after Ney Nozzle "T" mod, I inspected the cam & lifters, which is easy to do since the lifters are not mushroom headed and can be removed without splitting the case.
Remove the valve covers, rocker arms, push rods and tubes then you can use a piece of safety wire with a small hook in the end to catch the lifter snap-ring groove and pull the lifters out, don't use a magnet! H2ADs are notorious for "spalling" the cam and lifters, methinks you should do this inspection on every H2AD before any money changes hands. Obviously, you don't want to mix these parts up, put everything back where it came from, these parts have become "close friends"!
Some H2ADs don't have an oil filter, just a screen (25hr oil change) and they all require the Lycoming "Snake-Oil" additive, unless you use Aeroshell 15W50 (or some others) which already has it added in.
I installed the Reiff block-heater from Van's and always preheat the engine before starting if it's below freezing.
I shouldn't say this because I may not be able to find another great deal next time, but this has been a great engine so far! The dataplate says it's rated at 150hp at 2600 rpm (160hp @ 2700), the FP Sensenich red-line and I burn less than 8 gph WOT cruise at altitude.