Bravoman Posted February 22, 2014 Report Posted February 22, 2014 I was wondering what y'all thought about the best thing to do in the climb so far as leaning goes. After takeoff and getting configured, I am leaning to about 1480 tit and this yields about 25gph. My chts stay below 400, with the hottest usually about 385-390. I figure based on the chts that is not a bad set up(cowl flaps open of course). I haven't seen a post on this and thought it might be interesting to see how some of the other bravo drivers on this board managed the engine while climbing. Thanks, Frank
orionflt Posted February 22, 2014 Report Posted February 22, 2014 I lean in climb all the time, even if i'm only climbing a few thousand feet
Hank Posted February 22, 2014 Report Posted February 22, 2014 Target EGT is a good way to lean in the climb. If you are not familiar with the term, use the SEARCH bar--it has been extensively discussed here, and this is getting to be the time of year to collect your target. But then again, I don't know where KYYY is, so it may still be early there.
gjkirsch Posted February 22, 2014 Report Posted February 22, 2014 I lean to 1500 TIT in climb, watch oil temps (190's) and cylinder temps (360's). Cowl flap setting depends on outside temp.
carqwik Posted February 22, 2014 Report Posted February 22, 2014 I set cruise climb power after 1,000' AGL...34/2400 leaned to 1550 TIT. Yields about 23.5 gph...climbing at ~500+ fpm at 140 kts or so IAS. Cowl flaps set as required...which is full open in the summer in the desert until cooler air is reach; winter is typical 1/2 open to closed depending on OAT and engine temps. This is the cruise climb setting Bob Kromer recommended to me back in 2001...
Bravoman Posted February 23, 2014 Author Report Posted February 23, 2014 Target EGT is a good way to lean in the climb. If you are not familiar with the term, use the SEARCH bar--it has been extensively discussed here, and this is getting to be the time of year to collect your target. But then again, I don't know where KYYY is, so it may still be early there. Kryy is Cobb county airport just north of Atlanta. Close to where your'e moving
Hank Posted February 23, 2014 Report Posted February 23, 2014 Hot-lanta! Yes, it's time to collect baseline data for target EGT. The goal is to be as close to standard conditions and sea level as possible, and depart full rich. When you have time during initial climb, write down the EGT number. Then lean to that EGT in the future when conditions are different. Many people swear by this approach. Note, however, that this works well for NA aircraft, not sure that it transfers directly to turbocharged models. Someone here will know.
FlyDave Posted February 23, 2014 Report Posted February 23, 2014 I've had my Bravo since December so I'm still learning the airplane and turbocharging as well. I lean to keep TIT under 1600 and CHT's below 400. I have alerts set on the JPI if TIT goes over 1650 and CHT's go over 425. I religiously monitor temps.Also, I don't use the stock TIT gauge as it reads almost 100 degrees cooler than the JPI TIT display and the probes are in different places. What I have found is that I have to lean to TIT in the climb and CHT in cruise - that was backwards - lean to CHT in the climb and TIT in cruise. I climb full power to 1,000' AGL then throttle back to either 32"/2400 RPM or 29"/2400 RPM - depending on weight. I can easily maintain 500-800 FPM at these rates and keep the A/S up with the nose lower. This helps a lot in keeping CHT's down. Since I have only flown this airplane since December I don't have experience flying it in hot weather so I'll try to monitor this thread when it gets hot and we can compare notes then. Fly safe! Dave
carusoam Posted February 23, 2014 Report Posted February 23, 2014 It works so well for IO550s they put a line/range on the EGT guage for it. Analog guages get a blue zone, approximately 200dF ROP. The range is 100dF wide. G1000s only get a digital white zone. Climb procedure includes leaning and staying in the zone. So, while setting up using Hank's procedure, cross check and see where you numbers come out... The IO550s use an independent EGT sensor at the confluence of three individual exhausts on one side of the engine. Target EGT works! -a-
Hank Posted February 23, 2014 Report Posted February 23, 2014 Dave, don't wait for it to get hot. "Standard Atmospheric Conditions" are 59ºF and 29.92". That's where you will record your Target EGT [although you may use Taget TIT instead?], and match it during both warmer and colder weather. Where I'm busy leaving, winter morning climb rates can be fantastic. I saw >1500 fpm at 100 mph in my C a few weeks back in the afternoon--that's almost double the book rate.
jlunseth Posted February 24, 2014 Report Posted February 24, 2014 Target EGT is an NA technique not relevant to turbo ops. NA loses MP and therefore power as altitude is gained and must lean to keep the mixture from going over rich. Turbos make 100% HP and MP all the way to critical altitude. Over leaning is a good, quick way to kill a turbo, you can see some remarkable temps. GAMI/APS recommends 100%hp full rich to altitude which works well for me in my 231. That said, nothing wrong with a cruise climb leaned out a little so long as CHTs stay cool. 400 is my max for climb, and that would be one or two cylinders. If all are that high it is time to do something. Go richer though, not leaner, to cool temps. Leaner will have the opposite effect. I think you will find that in hot summer temps, such as phx in July, you will want full rich. I never see anything approaching 1600 tit at max rich. 1
Bravoman Posted February 25, 2014 Author Report Posted February 25, 2014 Target EGT is an NA technique not relevant to turbo ops. NA loses MP and therefore power as altitude is gained and must lean to keep the mixture from going over rich. Turbos make 100% HP and MP all the way to critical altitude. Over leaning is a good, quick way to kill a turbo, you can see some remarkable temps. GAMI/APS recommends 100%hp full rich to altitude which works well for me in my 231. That said, nothing wrong with a cruise climb leaned out a little so long as CHTs stay cool. 400 is my max for climb, and that would be one or two cylinders. If all are that high it is time to do something. Go richer though, not leaner, to cool temps. Leaner will have the opposite effect. I think you will find that in hot summer temps, such as phx in July, you will want full rich. I never see anything approaching 1600 tit at max rich. That is my understanding as well
donkaye, MCFI Posted February 27, 2014 Report Posted February 27, 2014 Agree, target EGTs are for NA engines only. An article was written in Flying back in 1992 regarding leaning in the climb for the TLS. At that time max recommended TIT in the climb was 1450. I never lean beyond that. I also don't reduce power below that to make the boost pump turn off until at altitude; Bob Krommer's recommendation. I'm on my second engine with the first one having gone to 2,300 hours before I voluntarily bought a reman because I fly instruments a lot.
carusoam Posted February 27, 2014 Report Posted February 27, 2014 That's clear, when the MP stays constant, there is no need to vary the mixture... With N/A engines, the MP is changing all the way up. Best regards, -a-
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