Nothing much has been done to it, just the Roosa Master pump upgrade, same as a late 880 and the 1600/early 1650s. The fuel is turned up obviously and the RPMS were around 2500 then. Backed it down now since it's retired from pulling. Those heads are terrible for flow, not much you can do to help them. Can get better results with the direct injection like in the 1655 we pull.
Seems to run good for a pretty much stock tractor. I always liked Olivers, even though we were a Farmall family. There were several nice 88s that I pulled against with our old M. Of course, there aren't too many antique tractors I don't like though lol.