This for all the engine experts out there. I am going to check my timing on my 65, to verifiy as being correct, but have this question.
For the first 1/2 of flight the engine has a rattle to it and then will go away. First I thought it was piston slap, but it has four new cyls and pistons and the time frame is all wrong for this rattle to happen . The lifters are quiet at start-up and seem to stay that way. I started wondering about the 1/2 hour time frame and thought it would take about that long for the mags to heat soak. If I have too much advance and the mag parts expand inside to cause a slight retarding of ignition. Is it possible I'm hearing detonation in the first half hour? Like I said, I will check out the timing and rule it out, but curious if some-one else has seen this happen? They are the older Bendix mags, not the box mags.