i have never worked with a lister/oid, however i have large engines and of course the s195 changfa
in development of the s195 for the trigenerator, i removed the hopper and installed the plate, and ontop of that an old tstat housing off a little honda car from a pikapart lot.
i put a radiator off a nissan sentra circa '87 or so
then i installed a bosch auxilliary heater pump, off an old audi from the pikapart lot
i used the same theory of operation typical of heavy trucks in that the tstat is used only to get the engine up to temperature as quickly as possible.
the tstat is a 195d F unit
the little pump moves maybe a gallon/minute as it is plumbed into the drain cock port at the bottom of the cylinder casting which is 1/4" pipe threaded.
the radiator is cooled by the oem nissan electric fan, which is controlled by the oem fan temp switch
the system runs under full load between 204 and 214 deg F, so the tstat stays open and does not regulate the engine temperature.
the engine is rated at 12hp continuous, but under a closed system that is controlled like this it will sustain 15hp continuous and burn cleanly with no smoke.
the only failure i had was a blown head gasket that a happened on the test stand when i forgot to turn on the switch that provided power to the fan. it ran up to 260F under full load and was running when i shut it down, didn't find out it had a blown head gasket until i let it cool down and tried to restart it.
new gasket, from an s1100 (an upgrade higher quality gasket that will fit) and back in business again.
i see no reason why this same theory of operation could not be applied to a lister/oid
it is my belief the controlling factor as to continuous hp rating is that it is limited to the type of cooling used, use a hopper or convection cooling and you have to derate, use a closed and controlled system and you can get more power output.
yes hopper or convection systems are simpler, however the argument that closed systems with pumps, fan's, radiators are prone to failure, is in my opinion not a well based assertion. modern pumps, fans, radiators and controls have proven to be very reliable and not prone to failures.
that is "if" one spends a little time to do things right.
i really believe that running these engine hotter makes a significant difference in the engines ability to burn more cleanly and by extension be more efficient.
so i like seeing folks working to include tstats, pumps, radiators and such to their lister/oids, i think there is much more that these engine are capable of delivering.
