Cirrus Turbonormalizing

Fly_Unity said:
as far as I know when your ROP, giving more fuel will decrease temps. Only when your on the backside of the Peak curve will the temps decrease when you lean. Today at 17 gph temps ran at at 400, when I slowly went to 16 gph temps did nothing but rise, so I went to 20 gph and got an instant drop down to 390, as I started to slowly pull it back from 20, the CHT's started to increase again. I tried the "blueline" LOP (the Garmin perspectives LOP recommended fuel flow) and no cooling there. Another note is that the hot cylinders were # 1 and 2 (the back ones) The rest of the 4 cylinders were only around 340.

Im not impressed with these covers, they do not provide even heat, when I took them off, every cylinder was within 30 degrees. Just talked with our Cirrus Service Center and he said NOT to use them unless they are enlarged. sigh... I will just go without them and try doing more of a power descent. Cirrus has a -20C temp limit? thats what it was at today.
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You are correct about the ROP, but I thought you said you were running LOP, which at 15-17gph you should be on the LOP side. Not familiar at all with those covers, sound like a problem to me.. And I will second your earlier wish for a spoiler, that would come in handy. I just looked in my CSIP software and the temp limit was -40. I have never had the need to know that before!! And it said for ever .5 gallon reduction of fuel flow from 17.0 you should expect 10 degree drop in CHT.
 
patthepilot said:
20GPH should be ROP, and peak being around 18.5 or 19. So leaning from 20 would only bring you higher CHTs. If you're at the base for LOP ops, 17.5, then lean, you'll already be on the lean side of peak. Have you run a GAMI lean test? I'd highly suggest doing one, and maybe you'll find injectors out of tune or maybe not even set up right. I can baby step you through everything, but honestly-in your descent where you say you're worried about staying in the green of 240 for your CHTs, it won't hurt the engine much cooler there. Also, as you say, keep the power up, or don't descend as quickly, start your descent farther out, or if you were running at 15.6 GPH, which is REAL lean, enrichen to 17.5 or slightly above, which is putting you closer to peak, but thus keeping CHTs hotter. The whole thing about "shock cooling" is a little silly, but I'll save that for a later time.
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Like I said Leaning works like a charm without the engine covers... 15.6 is what the Garmin Perspective has me lean to at 75% power at 16000 feet (50 degrees LOP). Peak is around 17.3 to 18 on the Cirrus I fly.
 
Fly_Unity said:
Like I said Leaning works like a charm without the engine covers... 15.6 is what the Garmin Perspective has me lean to at 75% power at 16000 feet (50 degrees LOP). Peak is around 17.3 to 18 on the Cirrus I fly.
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This guy may not be in a turbo. Anyways: 72 percent | 50 LOP | 14 GPH in a cirrus.

http://www.gami.com/articles/frugalflyer.php

About 60 to 65 percent through the video. You can go beyond 50 LOP though. If the engine is smooth bring it back to 75-100 and see how that plays out.
 
17.3 to 18 gph still sounds good. Is that the lower end of the garmin triangle? I know there is about a gallon of space the triangle says is correct. I'd really be interested in seeing a lean test and maybe a data download to make sure your engine (ie controller) are set up right. 15 just sounds too low. But that's very lop. Like 75 or 100 right?
 
roundout said:
Didn't mean to come off that way, sorry.
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No worries man, I was joking! I read the article like 4 years ago when the Acclaim first came out. I remember thinking "I'd love to fly one of those machines". It sounds like you've had the opportunity, and I am envious.
 
I worked for them until about 6 months ago when I got laid off. Pity, too, because I used to frequent the Mooney service center down at CXO when we had a sales office at DWH - I totally would have hooked you up with a "demonstration flight." Oh well, c'est la vie. I highly recommend begging, borrowing, or stealing a ride in one if you have the opportunity, though.
 
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