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I have recently bought a Rocket and would like some advice on climbing to altitude. I start off at full everything, and then after 1000 feet or two drop back to a manifold pressure of 35 and 2500 RPM. Even though I leave the mixture full rich and cowl flaps open, of course, I still find my hotest cylinder creeping above 380 and near 400 at a speed of 120 kts. Sometimes, perhaps I’ve gone a little slower than 120 kts. I end up having to speed up to 130 kts to get the temperatures to drop a bit, and my climbing rate plummets to about 600 ft./min. I am wondering what other people do. I am not sure that reducing from full throttle and full RPM actually runs any cooler, but it’s what I was taught. Thanks!

Hey all, Had a perfect day on Saturday to finally do some high altitude testing, both for the plane and my new oxygen canister (SkyOx with cannula). I took off from PDK (1000' elevation, 25°C) and climbed straight up to 17,500 to test climb performance. I used cruise-climb settings, adjusting VS to maintain 120 KIAS, and leaned for power using EGT. Then did straight line cruises from 17.5 down to 12.5 to measure speed and fuel flow. Also, used my pulse oximeter to test blood-ox levels. Performance charts are attached for those who are interested. This was just one test, on a day that was significantly hotter than ISA, so it will all be relative. Also, I started with 60 gals of gas and just me and on board, so I was probably 3000 lbs or so. But generally speaking, performance seems consistent with book numbers. A few of my key takeaways from the event: 1) The view from that high altitude was neat, a little freakish at first as I could really tell the difference once I got into the teens. Started to look like an airliner view. I'd never been that high in a personal plane before, but it was great once I got over the initial anxiety. 2) My plane just seems to like cruising in the mid 170s. Up high, that was about all I could get. Stayed ROP at that altitude because it really didn't like LOP, and at that altitude it doesn't really matter anyway. Down lower, I was able to get back to LOP which improved overall efficiency. 3) My oxygen delivery worked fine...when I remembered to breathe! I was so caught up in the data collection (and at first, yes, a bit nervous) that a few times when I slipped on the oximeter it was showing blood sat in the 80s. But a few deep breaths and I was able to keep that in the 90s, so now I know how that works! Overall, it was a fun experience and gave me some confidence for how to fly higher when conditions warrant. I will look to a winter day this season to repeat the test at ISA or lower and see how that changes things. Cheers!