ORIGINAL: airraptor
Generally 180+ on exhaust timing is pipe timing.
What is the measurement where the exhaust port close?
How wide is the exhaust port at the top?
How big is crank hole?
How big is carb? IE (.300 - .330) i think those are .310 on the TT
How is your crank measured? from BDC or TDC. I usually just got of when i can see light coming thru crank and use the back cover screw hole as a reference. The crank starts to open when near the screw hole at the 7 o-clock position and closes around the screw hole at 1 o-clock for around 180 degrees total. normally you want it to open around 40-50 degrees. I will dig in my boxes and get the numbers i have for you ok.
Oh year i think 16,000 is with in reach. on a jett pipe.
Shoot... I didnt even think of measuring this other stuff. I'm going to run the engine today to test my new boat but I will tear it apart again tomorrow maybe, and take those other measurements. I need to get a prop hub puller because the prop hub on this engine is a bear to get off.
I do know the carb throat is .290", and I made all of my measurements with the piston starting at TDC rotating the engine in normal CCW rotation towards BDC. I made my measurements using a 150 watt halogen light shining into the exhaust and backplate holes and made took measurements from when I could just barely see light shining through for open times and when light was just barely no longer visible. I would estimate my numbers to be within 1/2° +/-.
Thanks for getting back to me. I appreciate it. I'll get those numbers later on today or tomorrow morning and post them up. The crankshaft hole might be a little tricky since the crank is a pain to get out but I'll see what I can do.