bmcconnaha Posted January 3, 2022 Report Posted January 3, 2022 5 minutes ago, ArtVandelay said: I run 20°+ LOP, and at 13000’/2500 rpms will true out at 153 , but only burn 7.9 gph vs your 162knot/9.1 gph. I’m guessing if you ran LOP you’d lose 6-7 knots but would only burn 8.0-8.1. I like the efficiency of a 201 and it’s less about maximum speed, more about mpg. i fly occasionally LOP, especially if i have no where to be, or its bumpy and im slowing down anyways, but i havent messed with speeds LOP. when i have the G3x installed next month, ill run some more numbers. Quote
Ragsf15e Posted January 3, 2022 Report Posted January 3, 2022 8 minutes ago, ArtVandelay said: I was at 13000’, my guess is at 9gph you were about 7000’? Yeah, at some point 9gph isn’t the right solution. Go high enough and it’s peak. Higher and it’s just barely ROP. Probably won’t hurt anything since it’s a lower power setting but it’s not always the right place to be… Quote
skydvrboy Posted January 4, 2022 Report Posted January 4, 2022 You guys are all missing the easiest and cheapest way to gain 10kts... just push the nose down. You can easily gain 10kts or more with no investment (OK, a little fuel). Of course, the problem is that it's only a temporary solution. 1 Quote
Tx_Aggie Posted January 4, 2022 Author Report Posted January 4, 2022 10 hours ago, bmcconnaha said: @Tx_Aggie to answer your question on the 390, without speculation. Down lower, I’ve seen 169kts true. But, that is not usually where I fly. I’m usually 10k plus. Tough to say the exact number, because obviously testing on different days, and different weights. This is typical of a 14500 cruise for me. 100-125 ROP. The better improvement is how it climbs though. It’s a definite improvement there. I took off out of Sheridan WY with the old 360, with two people onboard and full tanks, and it was seriously not happy getting to ten. The last time I left Sheridan, I climbed to 14500 with a similar load and didn’t think twice. I wouldn’t go out of my way to replace the engine with a 390 solely for a speed gain, that’s throwing good money away. But, when it comes time to overhaul, I’d go that way again. I had the a3b6d engine in mine, and I wanted to get rid of that magneto arrangement anyways. The 390 actually was a couple grand less than the 360 a3b6 and almost 4K less than the a3b6d (lycoming factory rebuilt). I sold the oem prop to get the hartzell top prop, so it costs a few more grand in the grand scheme, it was definitely worth that. Common misconceptions that you’ll hear: cylinders cost more: they don’t its only ten horsepower: well the engines were certified at different times. The 390 makes 210hp or more. The 360 was rounded up. hopefully that helps you. with that said, other than removing an antenna or two, there will not be anymore money spent on speed on this airplane. In the end, it’s a J. It does what it does, and does it well enough. If I need to go faster, I’ll buy a bravo or a 252. Brian - I appreciate all your posts, both here and Facebook. I think I found my M20J about the same time you did or just after. Fortunately for me the previous owner paid for a factory reman io-360, I didn’t know the 390 was an option until I started seeing your posts. I really do enjoy mine and it’s perfect for flying below 10k with the family. I just wonder if I could squeeze a little more out of it. Thanks again! Quote
bmcconnaha Posted January 4, 2022 Report Posted January 4, 2022 2 hours ago, Tx_Aggie said: Brian - I appreciate all your posts, both here and Facebook. I think I found my M20J about the same time you did or just after. Fortunately for me the previous owner paid for a factory reman io-360, I didn’t know the 390 was an option until I started seeing your posts. I really do enjoy mine and it’s perfect for flying below 10k with the family. I just wonder if I could squeeze a little more out of it. Thanks again! If that 360 is fresh, I’d keep it and focus on the low hanging fruit. Perfect rigging. Clean up the antennas etc, and not go much further. If I had a 360, I’d highly consider the MT prop. For both it’s climb performance and it’s smoothness. Unfortunately, I hear it’s pretty tough to get your hands in the lopresti cowl. I really do like the 390, and especially like it up high, but it’s definitely not worth taking a relatively fresh engine out for one. Sounds like you’re enjoying your J. It seems the most expensive time is either when the airplanes down for maintenance and you can’t fly it, or the weathers bad, and you can’t fly it. I type that as Im browsing barons in another window, lol. 1 Quote
ArtVandelay Posted January 4, 2022 Report Posted January 4, 2022 Easiest way is to move to Montana, where the air is dry and cold, then lose as much weight as possible, you and the airplane. 1 Quote
larrynimmo Posted January 4, 2022 Report Posted January 4, 2022 I with help of ai I installed a Lycomming factory io360a3b6d in 2018…and it ran well, but not great numbers…the annual in 2021, with 450 hours on the engine, we sent out the mag to get it inspected…it cost $1,500 to get repairs done including replacing both coils. engine runs with EGTs at least 50 degrees colder LOP…much greater cruise speed at all power settings….and better fuel economy. my J had never really come close to book numbers…now I am. At 2500 rpm, 25.8mp 100rop I was able to achieve 165k true airspeed in both directions (2,300#) Quote
Tx_Aggie Posted January 4, 2022 Author Report Posted January 4, 2022 15 hours ago, Browncbr1 said: Save $100k and find a 231 with the turbo plus intercooler instead of a 252. Yeah I agree if I were to fly higher but that’s not an option for me with a toddler in the back. Plus I really don’t see any 231s filing or flying faster than me at 8000-12000 absent of a monster tail wind. I also think there’s something intangible value to be said for plane you know vs another plane you don’t know the hidden issues of. Quote
Hank Posted January 4, 2022 Report Posted January 4, 2022 6 minutes ago, Tx_Aggie said: I really don’t see any 231s filing or flying faster than me at 8000-12000 absent of a monster tail wind. That low, you won't. Turbo Mooneys are fast because tailwind are usually stronger in the teens. At 8-12K, speed differences are pretty small. Quote
StevenL757 Posted January 4, 2022 Report Posted January 4, 2022 20 hours ago, Ragsf15e said: Easiest way is to sell it and buy an ovation. 170kts, problem solved. You beat me to it. To @Tx_Aggie’s questions above, by the time you’ve spent on those upgrades (assuming they give the performance desired), you’re spending Ovation money and likely more. 1 Quote
aviatoreb Posted January 4, 2022 Report Posted January 4, 2022 19 hours ago, M20Doc said: I installed one of these, it helped my speeds quite a bit. I see your 201 cowl no longer fits. 2 Quote
aviatoreb Posted January 4, 2022 Report Posted January 4, 2022 Forget the IO390 - An IO550 M20J is truly quite fast - better than 190TAS in many examples. 3 Quote
jaylw314 Posted January 4, 2022 Report Posted January 4, 2022 FWIW, this would be a good time to start that New Years resolution to lose weight. The difference between the POH weight and the average American weight for two people can make for about 10 gallons of extra fuel! Quote
Guest Posted January 4, 2022 Report Posted January 4, 2022 10 hours ago, aviatoreb said: I see your 201 cowl no longer fits. That’s the trouble with these mods. I also discovered that my fuel tanks are now too small. I wish I’d just left the small engine in place. Clarence Quote
aviatoreb Posted January 5, 2022 Report Posted January 5, 2022 8 hours ago, jaylw314 said: FWIW, this would be a good time to start that New Years resolution to lose weight. The difference between the POH weight and the average American weight for two people can make for about 10 gallons of extra fuel! I don’t have the stc paperwork to loose weight. I might need to get a field approval. 1 Quote
aviatoreb Posted January 5, 2022 Report Posted January 5, 2022 2 hours ago, M20Doc said: That’s the trouble with these mods. I also discovered that my fuel tanks are now too small. I wish I’d just left the small engine in place. Clarence Oh my gosh - ok balance aside - we leave that problem for smarter minds - but can you imagine an M20J with 400hp?! I think the airframe would need to be strengthened - I hear they put gussets on the liquid rocket sporting 350hp. Maybe that would be enough for the mythical IO720 400hp. I bet it would be ... pretty fast. Quote
Hank Posted January 5, 2022 Report Posted January 5, 2022 2 hours ago, aviatoreb said: Oh my gosh - ok balance aside - we leave that problem for smarter minds - but can you imagine an M20J with 400hp?! I think the airframe would need to be strengthened - I hear they put gussets on the liquid rocket sporting 350hp. Maybe that would be enough for the mythical IO720 400hp. I bet it would be ... pretty fast. Wonder which would be faster, the Airspeed Indicator or movement of the Fuel Gage??? 1 1 Quote
jetdriven Posted January 5, 2022 Report Posted January 5, 2022 On 1/3/2022 at 1:43 PM, bmcconnaha said: Mine was removed from service because it was an oil leaker, not because it was tired. It had a relatively recent top OH before I bought it. Just wasn’t comfortable with the leaks, particularly ones I couldn’t find sources for. i bought the plane with the intention of overhauling it eventaully, i just moved the timeline up. looking at the current delays, i am glad i did. So, that’s most likely not the case on it not making full rated power. compressions were still strong when i pulled it. I do r doubt you have a fast J. But a couple of things. You have 129 for CAS but there’s a chart in the book that’s shows -2kt from IAS to CAS for correction. Apply that Also at 14.8 DA you’re making something like 55% hp. So the 390 is making 4hp more. Quote
aviatoreb Posted January 5, 2022 Report Posted January 5, 2022 8 hours ago, Hank said: Wonder which would be faster, the Airspeed Indicator or movement of the Fuel Gage??? Just needs enough fuel for one lap around the Reno course. It might be close... Quote
Shadrach Posted January 5, 2022 Report Posted January 5, 2022 On 1/3/2022 at 3:26 PM, Ragsf15e said: Yeah, at some point 9gph isn’t the right solution. Go high enough and it’s peak. Higher and it’s just barely ROP. Probably won’t hurt anything since it’s a lower power setting but it’s not always the right place to be… I cannot think of a cruise scenario in which 9GPH would be a dangerous or abusive power setting. Suboptimal? Yes. Abusive? notsomuch. Quote
Ragsf15e Posted January 5, 2022 Report Posted January 5, 2022 1 hour ago, Shadrach said: I cannot think of a cruise scenario in which 9GPH would be a dangerous or abusive power setting. Suboptimal? Yes. Abusive? notsomuch. Yeah I agree with that. I was just trying to point out that as you go higher, it might be say 25 ROP at 10,000’ or so. Not really doing much for you, but also not hurting anything since it’s a pretty low power setting. Might as well be at peak and be more efficient. Local flight school has a technique in their SR-20 to always pull mixture back to 9gph when flying radar vectors in instrument training. Saves the student the time of doing a proper lean for cruise so they can focus on learning instruments and saves the flight school gas $$ from flying around full rich. Except when students learn that’s all there is to know about leaning - full rich or 9gph, done. Not as good a technique at 10,500’ on cross country. Quote
Shadrach Posted January 5, 2022 Report Posted January 5, 2022 1 hour ago, Ragsf15e said: Yeah I agree with that. I was just trying to point out that as you go higher, it might be say 25 ROP at 10,000’ or so. Not really doing much for you, but also not hurting anything since it’s a pretty low power setting. Might as well be at peak and be more efficient. Local flight school has a technique in their SR-20 to always pull mixture back to 9gph when flying radar vectors in instrument training. Saves the student the time of doing a proper lean for cruise so they can focus on learning instruments and saves the flight school gas $$ from flying around full rich. Except when students learn that’s all there is to know about leaning - full rich or 9gph, done. Not as good a technique at 10,500’ on cross country. I get the downside but that can be mitigated later. As a “keep it simple stupid” way of simplifying a task not germane to instrument training, I think it’s brilliant. Whoever came up with the idea understands more about engine management than the flight schools I used. 2 Quote
Ragsf15e Posted January 5, 2022 Report Posted January 5, 2022 24 minutes ago, Shadrach said: I get the downside but that can be mitigated later. As a “keep it simple stupid” way of simplifying a task not germane to instrument training, I think it’s brilliant. Whoever came up with the idea understands more about engine management than the flight schools I used. Maybe, I think they were more worried about the $$$ from droning around at 14gph vs 9gph over a couple thousand hours. 1 Quote
Hank Posted January 5, 2022 Report Posted January 5, 2022 1 hour ago, Shadrach said: I get the downside but that can be mitigated later. As a “keep it simple stupid” way of simplifying a task not germane to instrument training, I think it’s brilliant. Whoever came up with the idea understands more about engine management than the flight schools I used. Whenever I'm on approach, I reduce MP and RPM to the Key Number appropriate for the altitude. No, the Key Number doesn't change (46 for my C), but how I get it does. Down low, that'll be 23"/2300, but if I'm up at 4500 msl, it'll be 22"/2400; both sum to 46. Then I lean to whatever my cruise EGT was, doesn't take long at all. Then I'm ready to slow down before FAF, but that long 10nm leg doesn't take forever . . . . Know your plane. Know your power settings. Be proficient. Quote
Tx_Aggie Posted October 16, 2022 Author Report Posted October 16, 2022 On 1/3/2022 at 1:55 PM, carusoam said: Find Bob’s M20E… Copy his details. Bob enjoyed chasing the finer details of speed and ownership… New cowl, new paint, rigged properly…. Engine OH’d, new prop, and the finest instrument panel… Method of paying… investing throughout retirement… enjoyed his AAPL… Today, Apple is enjoying its three trillion market capacity… Go Bob! Best regards, -a- Can you post a link? Quote
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