ORIGINAL: claserdesigns
Ok, the engine is rotating like it normally does, I have good spark, but I think the timing is way off.
When the piston is on top and it starts to go down it when I have my spark set. Should I set my spark before it TDC and full compression?
Yes the spark should go off on the upstroke of the compression stroke (both valves closed) about 28 degrees BEFORE TOP DEAD CENTER. The ignition timing should be very similar to a 2 stroke.
Note that 28 degrees would be FULL ADVANCE, and would only be there at higher RPM's but this is your base timing (if your EI unit is auto retarding). They do make both kinds of ignition modules (auto retarding and auto advancing)
An auto advancing EI unit would be set at 2-5 degrees BTDC (or there about).