On my IO360 the points open twice per rotation, at the mark 25 degrees before TDC and exactly 180 degrees beyond that mark. Well, 5 of the 6 mags I've been responsible for timing did that, within a half degree. One of the two new Slicks I recently installed in my S-1S has the second spark retarded about 2 degrees, so the timing light flashes at 182 degrees past the mark.
This seems wrong to me - I think it means on two cylinders one of the plugs is firing 2 degrees later than it should. There's no way to adjust the second firing - it's built into the cam. In the case of this Slick, I think the second cam lobe was machined incorrectly.
I tried asking the local engine shop about this, and couldn't seem to get the fellow to understand what I was talking about. But it could be that I don't understand this at all. I'd be grateful if someone would explain how I'm wrong (or confirm I'm right) before I take the mag in to have the cam replaced.
This seems wrong to me - I think it means on two cylinders one of the plugs is firing 2 degrees later than it should. There's no way to adjust the second firing - it's built into the cam. In the case of this Slick, I think the second cam lobe was machined incorrectly.
I tried asking the local engine shop about this, and couldn't seem to get the fellow to understand what I was talking about. But it could be that I don't understand this at all. I'd be grateful if someone would explain how I'm wrong (or confirm I'm right) before I take the mag in to have the cam replaced.
