A most impressive result. Indeed this is an engine with a PSRU in a real airplane thats doing very heavy duty work.
Indeed the water cooling is great at preventing shock cooling that glider tugs and jump planes are plagued with.
Now of course an RV is a different animal..fast and low drag is diffrent to the "stimp Pulling" type work the tug is doing..Probably more like what my tractor does than my RV..
One thing caught my eye and I agree with...Auto engines can be great as long as they are not messed with..I suffered years of poor reliability from a well known Soob 1.8 conversion...the valve guides kept falling out..In fact the thing tried to kill me three times...It was always the after market valve guides that engine "rebuilder" didn't know how to install correctly.
So I was left to find my own solution which I eventually did and the package was then very reliable. Like everything under the hood though, The chain is only as strong as the weakest link and made me think very hard before chosing another auto conversion.
But the upside is it looks like there is some superb development work being done with autos and maybe one day we'll have a drop in replacement that will be engineered to the point where is outshines the lyc and is half the cost!
Good job..
Frank