230 vs 231

M20J normally aspirated Four Cylinder Lycoming IO-360 200 HP M20K Turbo Charged Six Cylinder Continental TSIO-360 210 HP

Customer Paul E. was thinking of upgrading to a 201 over his modified F model and I suggested he consider the 231 for about the same money. Why? Because the 231 is one of the most under rated general aviation aircraft and about the same money as the 201. There have been times in my 201 when I would have traded the performance of the 231 at altitude plus all the money I had in the bank. Why? Because of the safety factor of a turbo. ICE!!!!!!! TURBULENCE!!!!!!! You can climb out of it in a 231 when at times and experience you cannot with normally aspirated. Most Mooney buyers are purchasing performance and economy, forgetting that the Mooney is about the safest aircraft in its class as well, but I’ve had ice in my 201 and could climb no further with the engine producing only about 55-60% power at altitude. I’ve had moderate to severe turbulence coming out of El Paso on a summer day and could not climb to above 18,000’ where the air was reporting severe smooth. The 231 can not only climb well above that altitude easily, but most of them after 1980 had oxygen on board so that you could breathe! Not only that, many 231’s have hot props and I have yet to find a 201 with a hot prop. The Mooney can carry ice with the best of them, but if your prop is loaded with ice, you will think the engine will shake itself off of the airframe………been there, done that! Brrrrrrrrrrrrrrrrrrr………..shiver………………

One other item to consider is that the average 231 is better equipped than the average 201. You simply gain more value for about the same money in today’s market. ;o)

So, here is the email response I had sent my customer and friend Paul Eaton of Atlanta who is considering moving up to a 201:

Paul, below is a link for review by MAPA on the differences between the 201 and 231. The article is full of good information but I strongly disagree on the amounts of differing operating costs they site for several reasons:

The TBO of the 231 is definitely 1800 while the 201 is 2000, however, I’ve flown a 231 with 2400 hours on the engine and it still ran strong as I have on a 201.

The author claims a significant difference in engine operating costs and I disagree providing the 231 operator knows how to power manage. My turbo buyers learn from me how to manage that engine. Everyone speaks of top overhauls with the Continental and I want to address this some. Whether your engine is the TSIO-360 GB (as found on many early 231’s), an LB (only a difference in fuel delivery, not in rod or case size, and you can nearly make a GB an LB by adding about ½ GPH to fuel flow) or even the highly touted 252 engine, the MB, my experience has shown basically the same thing on all three versions on Continental’s 210 HP turbo charged engine. That roughly half of all models require a top overhaul mid way to TBO, and about the same that make it to TBO without a top. What makes the difference? As always, THE PILOT! A good “power” manager considers his engine. It is true that a turbo charged engine can and will run a bit warmer than a non turbo charged engine. The Continental engine is designed to be a turbo charged engine. That is the same engine used in the twin Piper Seneca II which is the most sought after Seneca. Turbo charging the Lycoming i.e. the Turbo bullet was a mistake as that engine was not designed to be turbo charged. Those Mooney turbo pilots that like to fly way up with the airliners as a habit can fully expect to do a top half way to TBO. Those that fly at more reasonable levels such as at or below 14,000’ and watch engine temps, install Gami injectors, and follow a few more of my suggestions including waiting a full 5 minutes from touchdown prior to shutting the engine down and not over boosting the engine on take off, and not shock cooling the engine on descent, may enjoy getting to TBO without a top overhaul. Speaking of top overhauls, I need to mention this one thing: You do see a lot of turbo engines having a top overhaul midway to TBO, no doubt, however Continental engines have two hot cylinders (eliminated with Gami injectors) and the ever selling mechanic will suggest to his customer that two cylinders are bad, but you might as well do a complete top overhaul now so you don’t get plagued with more cylinder work later on……I ask, why do six cylinders when only two were necessary? That only adds to the cost of operation and does not increase the value of the plane. Buyers expect cylinders to be in good health, top or not. And, while on that subject, the Continental is a lower compression engine, therefore compressions of 45 pounds and above are acceptable for Continental whereby about 65 and above is acceptable for Lycoming. The main thing is that your engine compressions are within 20% of one another. Now, is the 201 engine a cooler performer than the 231? Not that I have seen. In the summer time, I routinely have to level off a climbing 201 for about 5-10 minutes to allow it to cool off enough to continue my climb. I have yet to have to level the 231 off for climb above 6,000’ in the summer. Some 231’s come equipped with after market inner-coolers, but they too are a plus and minus as most things in aviation are. While your engine will run cooler in summer which is good, it may run too cool in some winter applications. You must reach a minimum of 180 degrees of engine temperature in order to burn off water due to condensation or you risk rusting parts inside of your engine, and at times in winter, you will have trouble reaching that temperature which will equate to lessened engine life and that goes for all aircraft engines. Never just run them up on the ramp unless you plan on flying it up to normal engine temps! Even simply pulling the prop through can cause rust problems, so try to refrain from that in any airplane.

He compares the 201 vs 231 on an engine chart and shows money spent on a turbo overhaul though not done on the 201, yet forgets to take in to account that the 201 has a muffler that lasts about the same time as a 231’s turbo and at about the same cost and there is no muffler to maintain on the 231 at all. That’s a push!

He also does not take in to account that for any given trip, the 231 out performs the 201 in not only cruise speeds, but in climb speed. What happens when you get to altitude and destination quicker???? Less time on your engine and airframe!!! Less time is less fuel, less engine/airframe time which all but makes up for the 200 hour difference in TBO and keeps values the same or higher due to less time. A faster plane also gets you there quicker. How much is your time worth?

We all need on occasion to fly high and nothing was taken in to consideration for an O2 system which most 231’s already have. Hot props were not available in the 201 and that can save you ass. I’m living proof of that!

I did a study when I owned my 201 and came up with reasonably the same costs of operation due to the faster plane of the two making things more equal. So, if you read between the lines, the 231 is the better plane in most regimes, handles better, easier to land, has more of a “larger airplane” and for all intents and purposes, the 231 simply does more.

You decide, but I would strongly recommend the 231 over the 201 any day. ABOVE ALL ELSE…….the 231 can be a safer airplane, and no more pesky hot start problems coupled with a smoother and quieter six cylinder engine. Note that both engines are 360 cubic inches, so a large displacement engine such as the Lycoming IO-360 is divided only between four instead of six cylinders makes for huge pistons which equates to huge explosions inside that engine cylinder which equates to more NOISE. All single engine aircraft are loud, but the six cylinder engine has a lower sound on the decibel meter and has less noisy result not to mention the smoothness of more cylinders. Ever driven a V-12 Jaguar? Smoooooooooth! At least when it’s running right which by reports is rare. :o) The more cylinders, the smoother the engine. Common sense.

The 231 is a lot more fun to fly. You have to fly one to see exactly why. The author of the MAPA article also didn’t mention the quieter, smoother engine which equates to less stress and fatigue for the pilot and passengers.

Please don’t anyone think that I am taking away from Mooney’s staple aircraft, the 201. It is a fine machine with no doubt, obviously the finest in its class. I owned one for over 5 years and loved it, it’s just that the trouble I got in to with it would have been a non issue had I had a turbo charged engine. The 231 also feels like the heavier airplane than the 201 which it is. More longitudinal control as well due to the longer airframe produced by the longer engine cowling as well as the extended tail feathers that were installed on the 231 to compensate for the longer, heavier engine. The 231 also has longer “leg’s” than the 201, so less fuel stops also equate to savings in time and money back to climb altitude. So much to consider that the author of the comparison article did not address. However, if I were in a financial position to once again own my own Mooney, I would use my 4,000+ Mooney hours and hundreds of inspection involvements to make my decision which would be to acquire a 231 over the 201.

Richard Zephro “zef”

www.mooneyland.com

http://www.mooneypilots.com/M20K231_Evaluation_Report.htm. The author was a good reviewer, but I disagree with some of the things he had to say, particularly about operating costs being as significant as he states. Gami injectors are far more affective on the Continental engine vs the Lycoming, so consider adding Gamis which will pay for themselves over and over in the 231, not to mention the possibility of eliminating the 2 hot cylinders and perhaps a future top overhaul. www.gami.com for more information.

AS A FOLLOW UP, SINCE I WROTE THIS HEAVILY READ ARTICLE; DEMAND, SALES, AND PRICING ARE WAY UP ON THE MOONEY M20-K/231 AND UNFORTUNATELY MORE DIFFICULT TO FIND....OH WELL. IT HAD TO BE SAID THAT THE 231 IS ONE OF AVIATION'S BEST KEPT SECRETS!

There is Nothing like a MOONEY.....Turbo or Not!!