That's good to know K2 and very true but this engine has sealed ball bearings except for the rod that has a roller bearing.
As I said before I was going to try to bend some exhaust pipes. After two days of failures I built a special bender just for this tubing size. Having the right size dies helped a lot and annealing the pipe helped too but packing the tubing with damp fine sand made the biggest improvement. I mean really pack the sand in using a steel rod and a hammer.
The quality of my brass tubing was very poor and when annealing the tube it showed defects in the material so I decided to paint the pipes to cover up the defects and the engine needed a little more color anyway.
I made up 5 of these that screw into the cylinder heads.
The tubes go over the outside with a close fit. I made some brass collars 1/4 in thick with a set screw in them and they fit over the pipes next to the head. Tightening the set screw locks the pipe in place but still allows the repositioning of the tube if needed. (sorry I forgot the pictures)
A few Pictures with the prop installed.
Number 3 cylinder pipe has an additional bend to direct the exhaust to the side.
I bought 6 feet of brass tubing and ended up with 5 pipes 6" long the rest was scraped.
I have learned one think from this I am not a tubing bender person so I will have to find a different way to make the intake runners.
Thanks for looking