hypertech Posted July 25, 2019 Report Share Posted July 25, 2019 That's what I thought but they also spec I think 27.2 for the max fuel flow and that's not enough so not every spec is right in practice. Wondering what others are actually running at. The MSC supposed checked everything but this is where the idle is on mine now. Wondering if that's right in the real world for the 310 hp version to keep it from stalling on roll out or if I need to take it back. Quote Link to comment Share on other sites More sharing options...
kortopates Posted July 25, 2019 Report Share Posted July 25, 2019 3 hours ago, hypertech said: That's what I thought but they also spec I think 27.2 for the max fuel flow and that's not enough so not every spec is right in practice. Wondering what others are actually running at. The MSC supposed checked everything but this is where the idle is on mine now. Wondering if that's right in the real world for the 310 hp version to keep it from stalling on roll out or if I need to take it back. Actually TCM spec for the IO-550-N - the 310HP Mooney variant and now the 03, is 25.6 - 27.3 GPH. We at Savvy, and many others in the industry such as RAM, all suggest that MAX FF should be set to 0.5 to 1.0 GPH above TCM's high number and thus would recommend 27.8 to 28.3 GPH. Many owners though prefer as much as a gallon/hour higher. Since A&P's are bound by the manufacturer spec's not all maintainers and repair stations are willing to go above TCM spec's; especially by much more than 1 GPH. But because its a accepted industry standard most will go by our recommendation. Problem is as you go higher, you'll get some CHT relief at the cost of decreasing the horsepower the engine is delivering from being overly rich. Nobody wants to be held liable if the pilot has a takeoff accident cutting it too close and then the FAA violates them for for improper maintenance or worse the estate wants to sue them. But as mentioned above, the idle adjustment is entirely independent. Running 29 GPH for MAX FF will not prevent a smooth 600 rpm idle, but the idle adjustments must be re-done after adjusting the higher end adjustments and vice versa. An Idle 830 rpm vs spec 600 rpm idle will substantially increase short field landing distance. 2 Quote Link to comment Share on other sites More sharing options...
ilovecornfields Posted July 25, 2019 Report Share Posted July 25, 2019 1 hour ago, kortopates said: An Idle 830 rpm vs spec 600 rpm idle will substantially increase short field landing distance. Don't ask me how I know this is true! 1 1 Quote Link to comment Share on other sites More sharing options...
Niko182 Posted July 25, 2019 Report Share Posted July 25, 2019 Just now, ilovecornfields said: Don't ask me how I know this is true! my engine idles at around 900. How would I get it to Idle around 600? Quote Link to comment Share on other sites More sharing options...
ilovecornfields Posted July 25, 2019 Report Share Posted July 25, 2019 Just now, Niko182 said: my engine idles at around 900. How would I get it to Idle around 600? Well, you can do what I did and fly with @kortopates and have him point out that your idle speed is way too high, then go to the MSC and have them adjust the idle. I went to Top Gun. It actually tuned out that there was a metal piece on the throttle cable that was getting stuck so when I pulled the throttle control to idle, it wasn't really coming back all the way. Top Gun adjusted it for me. I don't know the technical details but I was well worth a trip to Stockton. 1 Quote Link to comment Share on other sites More sharing options...
Niko182 Posted July 25, 2019 Report Share Posted July 25, 2019 5 minutes ago, ilovecornfields said: Well, you can do what I did and fly with @kortopates and have him point out that your idle speed is way too high, then go to the MSC and have them adjust the idle. I went to Top Gun. It actually tuned out that there was a metal piece on the throttle cable that was getting stuck so when I pulled the throttle control to idle, it wasn't really coming back all the way. Top Gun adjusted it for me. I don't know the technical details but I was well worth a trip to Stockton. Okay. I'll probably bring it to Foothill aviation and have them Adjust it. I need my fuel flow increased too. It's usually around 27.0 right now and During hot days, I end up getting CHT's around 375 on takeoff. I'd like it to be 28GPH. Also, how much of a decrease in Landing distance will I get with 600 Idle? I can usually have the plane stopped in 800ft from the start of the runway with the idle around 900 to 1000. Quote Link to comment Share on other sites More sharing options...
kortopates Posted July 25, 2019 Report Share Posted July 25, 2019 2 hours ago, Niko182 said: Okay. I'll probably bring it to Foothill aviation and have them Adjust it. I need my fuel flow increased too. It's usually around 27.0 right now and During hot days, I end up getting CHT's around 375 on takeoff. I'd like it to be 28GPH. Also, how much of a decrease in Landing distance will I get with 600 Idle? I can usually have the plane stopped in 800ft from the start of the runway with the idle around 900 to 1000. A bit over 28 would be nice. I don't know how to quantify the increased landing distance, but suffice to say you will really notice the difference. Its not hard to beat book landing distances in the Mooney. Most of the Mooney landing distance performance numbers are based on 1.3 of Vso, based on weight. Lots of ways for a Savvy experienced mooney pilot to improve on the book numbers. But whatever the pilot is comfortable at doing, their numbers will improve with a properly set idle; plus it will save your brakes. Quote Link to comment Share on other sites More sharing options...
hypertech Posted July 26, 2019 Report Share Posted July 26, 2019 4 hours ago, Niko182 said: Also, how much of a decrease in Landing distance will I get with 600 Idle? I can usually have the plane stopped in 800ft from the start of the runway with the idle around 900 to 1000. Do you have some kind of STOL kit on there? If you are stopped by 800 ft from the threshold, I'm not sure you can get much shorter. The book landing distance is like 1100 ft and that's if everything is on a book perfect day. Quote Link to comment Share on other sites More sharing options...
Niko182 Posted July 26, 2019 Report Share Posted July 26, 2019 13 minutes ago, hypertech said: Do you have some kind of STOL kit on there? If you are stopped by 800 ft from the threshold, I'm not sure you can get much shorter. The book landing distance is like 1100 ft and that's if everything is on a book perfect day. 800ft is me with 45 gallons in the tank. 75 approach speed. 68 to 70 over the numbers. The moment the wheels touch flaps up, and full brake. It stops really quickly that way. Quote Link to comment Share on other sites More sharing options...
carusoam Posted July 26, 2019 Report Share Posted July 26, 2019 Things to consider... 1) Slowest rpm at idle is good... 2) Typically the manufacturer gives a spec that keeps the engine running under most conditions at the slowest rpm... 3) At such a low RPM, the plane will sink at a pretty high rate... 4) As PIC, you may find a higher rpm is something you use often... 5) In some cases... a low rpm choice is desired. 6) With a twistable vernier throttle... a few flicks of the wrist... and voila... more rpm arrives... (off Governor at low throttle setting) 7) Go with as low of an idle rpm setting as you can get, that keeps the engine running... 8) Add more MP by adding a measurable amount of twists of the throttle... There is an aircraft write up that mentions adjusting FF for the Screamin’ Eagle... in the 29 to 30gph range... Interesting, as it is significantly higher than the STC’s description... I was pleasantly surprised by my maintenance guy who was a bit reluctant to raise the max FF... Realistically, as Mr. Kortopates pointed out... check the T/O distances and climb rates before and after any FF changes... Using a decent method like CloudAhoy or other... don’t be surprised by more FF showing up as less HP than expected... PP thoughts only, not a mechanic... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
FlyingScot Posted August 7, 2019 Author Report Share Posted August 7, 2019 Thanks to everyone for your help on this topic - dropped my O2 off today to have the conversion done - will post a PIREP when done and after experiencing O3 power! - Bob Quote Link to comment Share on other sites More sharing options...
MIm20c Posted August 7, 2019 Report Share Posted August 7, 2019 It’s nice in the summer but the climb performance is amazing during our cold MI winters. Did they give you a trade in on your old prop? Back when we did ours it covered a good chunk of the new one. 1 Quote Link to comment Share on other sites More sharing options...
StevenL757 Posted August 7, 2019 Report Share Posted August 7, 2019 28 minutes ago, FlyingScot said: Thanks to everyone for your help on this topic - dropped my O2 off today to have the conversion done - will post a PIREP when done and after experiencing O3 power! - Bob As Anthony @carusoam said, I’m a little late to the party, but this has largely been covered. Good feedback overall. I’m glad you’re in for the upgrade. You will certainly smile when you push the power up the first time post-upgrade. You won’t believe it. Congratulations on the decision. :-) Steve 1 1 Quote Link to comment Share on other sites More sharing options...
FlyingScot Posted August 7, 2019 Author Report Share Posted August 7, 2019 22 minutes ago, MIm20c said: It’s nice in the summer but the climb performance is amazing during our cold MI winters. Did they give you a trade in on your old prop? Back when we did ours it covered a good chunk of the new one. I'm sure it it will go up like a rocket below 0 OAT! I did the top-prop conversion a while ago and that in and of itself was a huge improvement. When I did, they wouldn't give any trade-in value for my 2-blade MC. It's in the hangar, and I'm trying to think about what to do with it. It's in good shape (~1100 hrs), w/recent annual. Maybe a wall decoration? ;-) Quote Link to comment Share on other sites More sharing options...
Niko182 Posted August 8, 2019 Report Share Posted August 8, 2019 1 hour ago, FlyingScot said: I'm sure it it will go up like a rocket below 0 OAT! I did the top-prop conversion a while ago and that in and of itself was a huge improvement. When I did, they wouldn't give any trade-in value for my 2-blade MC. It's in the hangar, and I'm trying to think about what to do with it. It's in good shape (~1100 hrs), w/recent annual. Maybe a wall decoration? ;-) I got rid of mine for 2 blad mc for 1800 and got the top prop for 1900. A shop in bakersfield bought the 2 blade and i took that money and ran. I didnt think id get more than 800 for it. It was also leaking a ton of oil and red dy. Quote Link to comment Share on other sites More sharing options...
carusoam Posted August 8, 2019 Report Share Posted August 8, 2019 8 hours ago, FlyingScot said: I'm sure it it will go up like a rocket below 0 OAT! I did the top-prop conversion a while ago and that in and of itself was a huge improvement. When I did, they wouldn't give any trade-in value for my 2-blade MC. It's in the hangar, and I'm trying to think about what to do with it. It's in good shape (~1100 hrs), w/recent annual. Maybe a wall decoration? ;-) We have a prop guy around here... see @Cody Stallings for additional ideas... Best regards, -a- 2 Quote Link to comment Share on other sites More sharing options...
MIm20c Posted August 8, 2019 Report Share Posted August 8, 2019 9 hours ago, Niko182 said: I got rid of mine for 2 blad mc for 1800 and got the top prop for 1900. A shop in bakersfield bought the 2 blade and i took that money and ran. I didnt think id get more than 800 for it. It was also leaking a ton of oil and red dy. $1900 for a top prop...that’s a crazy good deal! Did you meet the seller just outside of an airport late at night? Did you have to bring your own tools to remove it off “his” plane Quote Link to comment Share on other sites More sharing options...
FlyingScot Posted September 5, 2019 Author Report Share Posted September 5, 2019 OK - the 310HP conversion is done - prop is balanced and the governor hits exactly 2700. I am here to tell you that what y'all said about it is definitely true - a different airplane on the takeoff roll - pushes you back in the seat. Without much optimization, takeoff roll was reduced by at least a third, and initial climb performance is just as impressive. All in, I missed a chunk of great flying weather while it was in the shop - but it was worth it. FF is at 28.5 and CHT's are nice and reasonable. Only draw back is my idle stall has returned; it's not idling too low (700-ish), it is apparently too rich, given I need to lean it out when I taxi to get a smooth running engine. Something to adjust at the next oil change; I am based in a class C, so stalling can be awkward depending on field location. Thanks to all of you for your advice on this - I know it is going to be well worth it on the shorter, high DA (carrier) airports I sometimes use. - Bob 4 Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 6, 2019 Report Share Posted September 6, 2019 Bob, What is your FF at 1k rpm? And at idle? full rich... around 4gph...? leaned... around 2gph...? This time of year... cold starts may require running the fuel pump until the engine warms a bit... Fuzzy PP memories only, not a mechanic.... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
FlyingScot Posted September 6, 2019 Author Report Share Posted September 6, 2019 11 hours ago, carusoam said: Bob, What is your FF at 1k rpm? And at idle? full rich... around 4gph...? leaned... around 2gph...? This time of year... cold starts may require running the fuel pump until the engine warms a bit... Fuzzy PP memories only, not a mechanic.... Best regards, -a- This weekend I will make note of these - starts are fine - just a problem with a hot engine at the end of flight - acts like vapor lock. - I will return with the numbers - thanks! Quote Link to comment Share on other sites More sharing options...
ilovecornfields Posted September 6, 2019 Report Share Posted September 6, 2019 21 hours ago, FlyingScot said: OK - the 310HP conversion is done - prop is balanced and the governor hits exactly 2700. I am here to tell you that what y'all said about it is definitely true - a different airplane on the takeoff roll - pushes you back in the seat. Without much optimization, takeoff roll was reduced by at least a third, and initial climb performance is just as impressive. All in, I missed a chunk of great flying weather while it was in the shop - but it was worth it. FF is at 28.5 and CHT's are nice and reasonable. Only draw back is my idle stall has returned; it's not idling too low (700-ish), it is apparently too rich, given I need to lean it out when I taxi to get a smooth running engine. Something to adjust at the next oil change; I am based in a class C, so stalling can be awkward depending on field location. Thanks to all of you for your advice on this - I know it is going to be well worth it on the shorter, high DA (carrier) airports I sometimes use. - Bob I hope @kortopates will correct me if I’m wrong, but I believe the IO-550 has two fuel flow adjustments, and when you change one it can affect the other. You probably need your idle fuel flow adjusted. 1 Quote Link to comment Share on other sites More sharing options...
kortopates Posted September 6, 2019 Report Share Posted September 6, 2019 49 minutes ago, ilovecornfields said: I hope @kortopates will correct me if I’m wrong, but I believe the IO-550 has two fuel flow adjustments, and when you change one it can affect the other. You probably need your idle fuel flow adjusted. correct, but actually three, when you include the idle mixture with the low unmetered fuel pressure and the high metered fuel pressure. But changing either will often necessitate a change to the other and then you iterate till everything is perfect. You're night about the issue as well, the OP's complaint on idle stall is almost always a combination of idle mixture and the low unmetered fuel pressure - sounds like they only got half of it right when they did the 310HP setup. 2 1 Quote Link to comment Share on other sites More sharing options...
Niko182 Posted November 26, 2019 Report Share Posted November 26, 2019 I found out today from that idle rpm change, idle rpm fuel flow, and Full power fuel flow are all easily adjustable. both the idle settings can be adjusted using a flat head. the idle rpm adjustment is a screw with a spring located at number 3. a friend of mine who also has an eagle had no problem adjusting his idle from 850 - 900rpm to 600 - 650rpm. it took about 2 turns. idle fuel flow didn't need to be adjusted. to increase the FF at 100% power, a 5/32 L shaped allen key is needed, and a 1/4 clockwise turn yields an increase of about .7 gallons per hour. you need a small allen key that will fit behind the oil filer. there is some safety wire blocking the entry hole but its not really in the way. after you're done, go to the runnup and check and make sure everything is working as properly. My friend did this. I would never do this because I'm not an A&P. for those of you that also don't want to do this, this applies to Acclaims, ovations, and eagles. 1 Quote Link to comment Share on other sites More sharing options...
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