flysamo Posted December 22, 2018 Report Share Posted December 22, 2018 Have ordered Hartzell top prop for 280 to 310 conversion, replacing a McCaully 3 blade prop, governor is a McCally set at 2550 , can this unit be reset for 2700 rpm , looks like fuel flow is to be reset at 25.6 to 27.3, engine instrument package has all ready been replaced with a JPI 900 which will have to be adjusted for conversion prop speed and fuel flow Quote Link to comment Share on other sites More sharing options...
carusoam Posted December 22, 2018 Report Share Posted December 22, 2018 Reading the STC supplies the answer to what is needed and what needs to be set up... Do you have a copy? The only thing fuzzy about the STC is the FF range.... it is like using 50°ROP... it works, but another 1-2gph more can be better for the CHTs.... Technically, there are two STCs, one is for the 310hp, and the other may be for the TopProp..? The cool thing about the STC, it also has all the performance data.... T/O and climb are most interesting.... Unfortunately, I don’t remember if the McCauley can be re-used... my Mac got damaged, that was the beginning of my research when doing the conversion... It would be great to collect some data... 310hp with... McCauley Hartzell TopProp A good chunk of the performance comes from the extra 200rpm and the extra gallons of FF... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
flysamo Posted December 22, 2018 Author Report Share Posted December 22, 2018 using the top prop stc Hartzell for f77498 acclaim type S thin blade, installing the JPI 900 we lost weight with the conversion and moritz was un repairable. Jpi will have to be readjusted and the prop is in the mail, some time in late January. trying to beat the usually year end cost increase. Ran a before test with the McCally at 11000 ' fuel flow 14.9gpm, 2470 rpm @ 3 degrees with 4 way ground speed avg. was 178.5. with AC equipped. would like to see results for $ spent. Looked at the carbon fiber props , decided on metal blades, but love the looks of the 4 blade( trophy prop vs one I can live with)). Cost was a big factor vs speed gained, and looking at my 1000 hr. prop wear helped make a choice. will be doing some test flights with the different Mods and how speed has changed. What is the best altitude/vs speed for the ovation for a test comparison 1 Quote Link to comment Share on other sites More sharing options...
Guest Posted December 22, 2018 Report Share Posted December 22, 2018 I believe that your governor has to go to a shop to be modified to 2700 RPM. Clarence Quote Link to comment Share on other sites More sharing options...
LANCECASPER Posted December 22, 2018 Report Share Posted December 22, 2018 On 12/22/2018 at 10:39 AM, flysamo said: Have ordered Hartzell top prop for 280 to 310 conversion, replacing a McCaully 3 blade prop, governor is a McCally set at 2550 , can this unit be reset for 2700 rpm , looks like fuel flow is to be reset at 25.6 to 27.3, engine instrument package has all ready been replaced with a JPI 900 which will have to be adjusted for conversion prop speed and fuel flow On 12/22/2018 at 12:30 PM, M20Doc said: I believe that your governor has to go to a shop to be modified to 2700 RPM. Clarence Plus you need to buy the 310hp STC from Mooney for $4995. Quote Link to comment Share on other sites More sharing options...
carusoam Posted December 22, 2018 Report Share Posted December 22, 2018 As far as the Governor goes... The original 280hp O1 was set to be operated at 2500rpm... I got a factory reman IO550N that came with its Gov already set @2700rpm... A JPI 900 is a great alternative... to failing gauges. I also got the Acclaim version thin blades. The N, and the thin blades, are pretty good at keeping WnB in check... MT hadn’t finished the STC for the O when I was buying... (off by a few months...) The TopProp is also available in composite structure. That would be a next step if WnB were a concern... (front seat weight balancing) Technically, charley weights in the back are there for a reason... (nobody likes adding to them... UL and speed robbing) As for best altitude for all out speed.... that is a balance between... power generated wind resistance incurred do a good WnB to be near the back of the envelope. Further back reduces tail drag... NA engines lose a significant amount of power with altitude compared to the wind resistance diminishing... 7 to 8k’ is probably the place to be... and that may be a DA concern, temperature related... PP thoughts only, not a CFI.... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
buddy Posted December 22, 2018 Report Share Posted December 22, 2018 I have the 310 hp conversation and found that 29.8 - 30 FF was better cooling for the CHT’s. 1 Quote Link to comment Share on other sites More sharing options...
Niko182 Posted December 22, 2018 Report Share Posted December 22, 2018 If you need to Buy the STC still, I recommend buying from @AGL Aviation. Mooney doesn't sell the STC anymore, and they let shops sell it for them so shops mark up the price as much as they want. A quite popular shop in northern Cali quoted me 7300 without tax for then STC and another shop charged me 6300. AGL was the only shop I found quoting it at its retail price of 4995. And if you live outside of NC, theres no sales tax. +1 to AGL also when adjusting the Fuel flow, tell them to set it at the max of 27.3GPH. dont waste your or their time slowly adding fuel. Most likely you'll need more than 27.3 GPH, but its a good starting point. The top props on the ovations really shine at between 10 and 12k. At least mine does. At 8k they can probably fly faster but you really need to burn gas. like 18GPH to see around 187 to 190. At 11 to 12k, I can fly WOT at around 15GPH doing 183 to 184. The prop was meant to shine at around 15k but that altitude The ovation doesn't have the power the Acclaim does. The 2700RPM on takeoff is nice, but its quite noisy. The takeoff performance is insane however. At full gross I get off the ground in about 1000ft. I climb cruise and descend at 2450RPM, as that frequency resonates with the A20 headset I have and it becomes really quiet. 2 Quote Link to comment Share on other sites More sharing options...
MIm20c Posted December 22, 2018 Report Share Posted December 22, 2018 Don also sells the stc for 5k. The governor needs to be sent in to have a different spring put in. The jpi will reset your 900 but if it actually turns 2700, or the FF is set high enough to keep full power on the climb without toasting the cylinders, it will give redline alerts on every takeoff. 1 Quote Link to comment Share on other sites More sharing options...
StevenL757 Posted December 22, 2018 Report Share Posted December 22, 2018 4 hours ago, flysamo said: using the top prop stc Hartzell for f77498 acclaim type S thin blade, installing the JPI 900 we lost weight with the conversion and moritz was un repairable. Jpi will have to be readjusted and the prop is in the mail, some time in late January. trying to beat the usually year end cost increase. Ran a before test with the McCally at 11000 ' fuel flow 14.9gpm, 2470 rpm @ 3 degrees with 4 way ground speed avg. was 178.5. with AC equipped. would like to see results for $ spent. Looked at the carbon fiber props , decided on metal blades, but love the looks of the 4 blade( trophy prop vs one I can live with)). Cost was a big factor vs speed gained, and looking at my 1000 hr. prop wear helped make a choice. will be doing some test flights with the different Mods and how speed has changed. What is the best altitude/vs speed for the ovation for a test comparison To answer your original question first - As you have the McCauley governor, the proper shop needs to perform a C290D3 /T20 upgrade, which allows the engine to output at 2700rpm. Depending on the age and condition of your governor, the shop will do a general inspection and may want to replace a few plastic parts with metal to support the upgrade, which I’d recommend. Keep your operating habits simple...takeoff should be accomplished at 2700rpm. Cruise optimal RPM is 2550. I worked closely with Bob Minnis (the original STC author and DER for the 310hp upgrade program) between 2012 and 2014 and he recommends this setting to maximize engine output while treating the engine as it should be treated. Not sure where you’re settling on 2470 or any other setting in cruise or descent planning. Also, although the 4-blade MT composite may allow you to shave off weight and increase UL, but will not give any performance improvement over the 7498 Hartzell. @Txbyker on this forum has one of these on his Ovation and could comment on its performance and any issues he may have encountered. To your last point, the best altitudes for the testing you indicate is between 8000 and 10000. Please take some time to post some details on your aircraft, where you’re from, and your mission type. Welcome to the forum. Steve 2 Quote Link to comment Share on other sites More sharing options...
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