Need M20F LOP stats.

[Lood]

Is there someone here that flies a M20F, preferably a '67 model, LOP? If possible, I'd like the figures in terms of average fuel consumption and TAS at 7-9k feet, please. If I can also get the average CHT's and EGT's, it would be a bonus. I have a test that I want to do on my '67 F and would like to compare the end results.

[danb35]

I fly my '67 F LOP and usually cruise in that altitude range.  I usually burn ~9 gph (full throttle, 2500 rpm), and get roughly 140 kts TAS.  I could get CHT/EGT data, but it'll take me at least until the weekend.

[podair]

Hi

I get pretty much the same numbers with a stock 1967 M20F with the 3 blade Hartzell.

For a variety of reasons it seems my ideal altitude is around 10,000ft. I normally cruise at 10,000 ft (my normal run is a 2h-2h30 flight), full throttle, 2500 rpm. I normally lean to peak or just 10-20 F lean of peak (no gamis). I get 33 litres per hour (just under 9gph) and pretty much invariably 145kt TAS. I check that on most flights with the e6b function of my handheld gps and that usually is off 125-130kt CAS indicated. I reckon that is around 68% power. 

A bit lower down, at 8k I'd say I would get similar TAS with about 36 litres.

At 12k I normally get around 140 tas for 30 litres.  

I have an EDM700 with fuel flow. More than happy to email you the downloads but no TAS or OAT on them. I emailed them to GAMI who confirmed I didn't need GAMIs as my injectors were balanced enough (my peaks are within a litre or two of each other). I don't normally lean any further than 20F LOP. normally keep just over peak, when I ve experimented any leaner I'd get a marked reduction in power and some hickups around -50F.

 

[MB_M20F]

I never even thought of running my F model LOP since it's so efficient ROP (148 KTAS 9 gph at 11,000 feet). I don't want to open up a whole can of worms here, but can someone tell me in three sentences or less why I should consider doing so?

[Lood]

Thanks for the replies. I usually set the mixture at 75 ROP, WOT and 2400rpm. This gives me around 140kts GS consuming 38 liters or 10 gal/hour. Highest EGT and CHT are in the region of 1400 deg and 340 deg. I'm planning to use my normal settings as above and then throttle back to say 34 liters or 9 gal/ hour and see what the speed and temps does and compare that with the same returns for LOP settings. Just want to do it out of curiousity.

[Qwalton]

Quote: MB_M20F

I don't want to open up a whole can of worms here, but can someone tell me in three sentences or less why I should consider doing so?

[danb35]

That last post was me--looks like that bug on this board still isn't fixed.