I finally got around to pulling and tearing down the 360 that I built last year for my '70 Challenger. It ran like a top but smoked on hard acceleration and used a bit of oil. I assumed the rings hadn't seated.

When I tore it apart, I noticed a lot of oil in the intake runners, backs of the valves are pretty built up with crap, and the tops of the pistons are nasty (pic). These were all new last year and only have about 4k miles on them.

What did I miss? Did the intake not seat properly? Valve seals/guides bad? The only part of the build that I'm not sure of are the heads. I bought them "done" from a private owner and really didn't pay a lot of attention to them other than a quick look at the seals...and they looked decent to me.

My thought is that I'll have my machinist check the surfaces on the heads and the intake, check out the guides, hone the block (it was bored .030 over when I did the initial build), and re-ring it.

Anything else I'm missing?