ORIGINAL: jef-lemmens
ORIGINAL: captinjohn
jef, I just started reading this very interesting thread on your engine build. Real nice work you do for sure. I was wondering about the port timing, is it the same as the engine you chose to build your own version of? I guess you may call it a ''piston'' port engine & not any reed valves. If you can, could you post photos of the rod as you machine it. Thanks Very Much, Capt,n
Hi Captinjohn , it is a piston ported engine (old school)
the porttiming of the new engine is 130° for the exhaust ( was 110° ) , 113° for the intake ( was 100° ) , 100° for the transfers ( was 90° ) , the compression ratio is now 6,7/1 ( was only 5/1 ) , in the future there will be certainly pictures of the rod construction , right now I can not post any picture , internal server error . You could always go and see at another construction report from me on a Dutch forum , there are pictures between of the rod construction
http://www.modelbouwforum.nl/forums/...eselmotor.html
Regards Jef
Many years ago when we used to race two strokes piston porting was it. First we modified it by installing reed valve blocks then machined holes in the piston skirt to increase the intake duration. I remember altering the floor of the intake port and the roof of the exhaust, machining some of the skirt and from the top of the pistons if there was enough room all in the quest for more performance. We burned a lot of candle wax late into the night just to get ready for next race day. We also made our fair share of boat anchors as well experimenting LOL. What fun it was when something worked and everyone else was set to scrambling to find out what you did. Ah those were the days.
Dennis