Old Race 340 Teardown

I have those same 810 castings for a future project, I really like the exhaust port shape on mine. I was told by Dave Koffel that these 810 castings were what he called "hand wiped" as they are smoother on the outside of the castings VS. the newer stuff which is rougher and some of the parting lines are sharp. I think the 810 castings were the ones that Bob Glidden used to modify when he ran the Arrow and had good success. As I remember Dave told me Glidden came out with a brand new engine combination with the Arrow and set the record at the first race !