I am pleased to report that after several years of promoting the idea, the club went with the 10 HP upgrade at TBO for our 1975 C-172M. While the engine reached TBO nicely, we were having problems with fouling some lower plugs on a very frequent basis for the last 6 months. This was most annoying. Got the call from Mattituck, and they report climb at 1,000 ft/min. This comes from a combination of: - Upgrade to a 160 HP engine - Repitching the prop (required with upgrade) - a tuned exhaust (Power Flow Systems). We went with a Lycoming Factory Remanufactured Zero Time engine. Spent money on a new "zero time" tach as well. (nearest 000) Budget was $22K Actual was $25K Over Bgt: $3K So we will end up with an assessment of $300 per member to cover the difference. Now I need to order 3 cases of mineral oil. Got a good source?