So when the engine suddenly lost power and started sounding like a bag of nails, I shut it straight down and feared the (expensive) worst. Having checked for obvous problems this morning, I couldn't find much amiss. Wet on the inside, dry on the outside, and the compression readings looked OK. I started her up for a few seconds - she ran, but sounded awful. Dave Gemzoe was kind enough to come around, and using his considerable engine building experience, set about looking for evidence of what the problem might be. Again, nothing obvious, so we tried to fire her up again. Outcome - one exhaust primary which had come loose, and nothing more Many, many thanks to Dave for having given up his time so freely. This fix was trivial, but the amount of engineering knowledge in Dave's head is astounding! So, a good end to a good weekend. Fantastic banter and competition in Class 3 as always. Particular congrats. to Danny Malkin and Jeff Smith for two spectacular runs!