Considering M20L AirMods conversion

[Davidv]

12 minutes ago, ArtVandelay said:

You should be closer to 10gph on the J otherwise you’ll be run very rich.

Thanks, I’m just going on how a friend runs theirs.  So you get 160 true on 10gph?

maybe it’s because my friend has a new engine, but when we start going below 12 gph ROP the CHTs are a little hot for my liking.

[ArtVandelay]

My previous ‘78 J wasn’t the fastest, but it would cruise at around 155 KTAS on 10.5 GPH ROP.  But I typically flew it at 8.5 GPH LOP at around 145 KTAS.  Later J models do a bit better.  A few might be able to do 160 KTAS on 10 GPH.  Anyone?

I do 150 on 8 LOP at 2500 RPMs and 9500’, which is actually below book because I’m well below MGW. I could do 160/10 at my typical weight if I pushed it which I did after overhaul to break it in. But I like the efficiency and cool cylinder temperatures (~330) of running LOP.

[1980Mooney]

5 hours ago, carusoam said:

Pretty tough comparisons…If you like LBs… this is the first one…… there is usually a mission difference that makes one slightly better for the end user over the other…

When comparing to the M20J… compare to the Missile that has the IO550(a) and 300hp…

Or the existing owner has an explanation for all the quirks that come with a modified plane…

This is a good point.  Just remember that you are contemplating buying a "unicorn".  It may make great financial and operational sense if it fits your "mission" and time horizon.  Basically M20L Modworks conversion, Rocket Engineering Missile 300 and M20S Eagle upgrades are potentially lower cost ways to acquire "Ovation" performance.  Each has its pros and cons.

On a M20L ModWorks conversion, from the firewall back you get a long body that is similar to the later long bodies so there is some commonality of parts.  From the firewall forward it is unique to ModWorks which has been long gone.  You are stuck with 2,900 lb. GW.  Granted that engine is TCM but things like corrosion on the engine mount could be a lot of trouble in the future.  Who has the drawings and specs?  As stated above there are only a few still airworthy.

Rocket Engineering did something similar with the Missile 300.  They took a midbody M20J and changed everything firewall forward by adding a 300 hp TCM IO-550A 300 hp.  Performance is similar to an Ovation in a shorter body. GW is 3,200 lbs.  I had one of the last conversions done back in 2001.  They did about 52 Missile conversions total I believe.  It has been fairly reliable and most are in service.  From the firewall back most M20J specs, part manuals, service manuals are online.  Due to the age of model certification lots of J parts are available direct from suppliers or salvage.  Rocket is still in business half days supporting the plane.  They have retained all the specs and drawings for the modification.  I recently had corrosion on the engine mount.  Rocket repaired it but it was not cheap and took a couple months.  The owner is now in his 70's so I have to be realistic about how much longer it will be supported.

If you can get this unicorn at a good price it may work out well.  I would be cautious about putting too much investment in it however.  If you plan to keep it for 20 years that is one thing but if you have to sell in the near future for unforeseen reasons it will be slow (that spells "discount").  I don't understand your comment about touch up paint coming off in the rain.  A new paint job will not make it go faster or increase your GW, but it will lighten your wallet.  I would buy it, maintain as necessary and then just fly the heck out of it.  

 

[KZNY]

On 9/14/2021 at 3:11 PM, bfreelove said:

Hello Ben,

There is another similar aircraft like yours for sale. I have been watching the forums on various stuff. Whats the useful load after full tank of gas (88 gallon tank). Is it 700+lbs useful load the number after filling up the tanks?

Thanks, KEN

 

 

I own N136MP and it's definitely not available... hahaha.  I haven't seen another M20L with the Mod Works conversion for sale in awhile.  I think there are only 6 that where converted that are still flying. 

 I've taken a lot of weight out of mine so I have 700 lbs useful load.  Not great but works for me. It has Monroy tanks so plenty of fuel, and electric speed brakes.  Makes a great long range single seater, or medium range two seater.  I have the back seats removed, they weigh 33 lbs so not much gained.  It also had the single level power removed and standard engine controls installed by the previous owner. 

I've been looking into the possibility of getting the gross weight increased through a couple different ways.  Not a huge priority for me though as I don't really need it.  

Feel free to PM if you have any other questions about the L as I did a bunch of research before I bought mine.  

-Ben