915IS Temps

Unfortunately you need to forget or unlearn the "rules" you have from a totally different engine.

This is a ROTAX you need to follow the 915IS engine manual not the Continental engine Manual.

The good news is that the ECU manages these things you are worried about you can ignore them...just relax and enjoy the flying

I agree with Glenn. Forget the other engine it's apples and oranges. Like comparing a VW car to another car. They both have wheels, engine's and they both get you to where you are going, but they are two different animals and need to be treated that way. learn about the 915 and do not compare maintenance and instrument numbers to another engine.

Read ALL the manuals on the 915 and follow them.

I agree they are very different engines. But if I flew per the Cirrus / Continental manual I’d be rebuilding my engine and turbo system every 1000 hours. Hopefully the Rotax recommendations are more inline with best practices for longevity not just best performance. My previous Rotax motors (912 and 914’s) were solid, but for a different mission. I flew them in gyros so not cruising at peak power all the time. The problem in the Cirrus / Continental manuals is that if you follow their guidelines you’ll be flying at 80% power which is great because you hit their published numbers, but mid to high 1600’s/ 1700f EGT will start to cause issues with most exhaust metals and turbo systems. 

I don’t love the idea of just trusting the computer without knowing what it’s doing, why, and when, but maybe that’s just what I have to do. An no, I don’t know or care what my truck ECU is doing. :)

The max EGT in the 915iS is 1742F, and typically you'll never get anywhere near that. I can run Max Continuous Power (95%) all day long and I'm usually 150 - 200F below that limit. However, I don't typically operate at MCP, other than in the climb. I usually cruise a Max ECO power, which is around 78-80%.

I used to fly SR22s, too. ECO power settings on the Rotax are analogous to LOP in your IO-550. Push the power higher than that and the ECU will go ROP. Forget about "Red Fin / Red Box" - the ECU takes care of all of that. 

Unlike the Continental world, top overhauls are virtually unheard of in the Rotax world. You're going to love this engine. A lot less to worry about than with the Continental!

Thanks! That’s great to hear! Looking forward to simple complexity vs complex simplicity. :)