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The top cowling on my 1977 J is going to need some fiberglass work in the not-too-distant future. It has a lot of spyder cracks, and the holes for the Camlock (or in my case, CLoc) fasteners are getting rather enlarged. I talked to a local aircraft paint shop. They said that it would be a very labor-intensive job. If I’m looking at thousands of dollars anyway, I might consider a Lopresti cowling. But I have no idea what they cost, or if they’re even available anymore. Anyone have any suggestions?

You might check with @Speed Merchant if he knows the current status of the LoPresti cowl, he is kinda familiar with it

I believe that Lopresti STCs are now owned by Whelen. It doesn't appear that they make the Mooney cowling any longer. But you could always contact them and ask. https://flywat.com/collections/aerodynamic-mods

+1 for wondering about the LoPresti cowl whereabouts/costs/availability (LASAR?). Amazing to see his cowl induction engineering influences in literally every production piston from Piper, Mooney, Cirrus. The only reason Textron/Cessna/Beech don't use his cowl designs is because they stopped aero engineering those designs when Gerald Ford left the White House.

Bob Kromer (former Mooney factory test pilot) has written that the M20J was optimized for 2500 rpm. Roy Lopresti did a lot of flight testing with a heavily instrumented airplane including a torque meter to measure actual engine power. I have no reason to doubt Bob's recollection. And when you say you are trying to pick the optimum rpm, you really have to determine what parameter you are trying to optimize: mpg or TAS. Or, maybe engine longevity? In reality, the slope of the curve (for whatever parameter you are trying to optimize) vs rpm is probably pretty flat in the vicinity of the maximum. In other words, the difference between 2500 and 2550 is probably negligible. A lot of people just go by what seems to produce the least vibration. The red box is a concept, not a hard rule. As the APS folks have pointed out, CHT is a proxy for cylinder stress. And as Mike Busch has pointed out that if you keep the CHTs under control you won't be in the red box. George Braly told me that he has never gotten any normally aspirated engine to detonate under any condition with a CHT of 400 deg F or below. He has gotten mild detonation at 430 deg F with elevated inlet air temp, 100LL at the low end of the allowable octane rating, sea level maximum MAP and mixture leaned to between peak EGT and 35 deg F ROP. So, you are not going to detonate an IO-360 unless you try really hard. Mike Busch told me that he cruises at fairly low powers (he guessed below 65%, but he doesn't calculate it so he doesn't know for sure). His rationale, and I quote, is, "I'm a longevity guy, not a speed guy," The airlines in the days of the radials cruised at around 55% BHP according to several flight manuals I looked at for the DC-3 and DC-6. All airplane performance calculations are based on the drag polar. Here is the actual M20J cruise drag polar I got from Lowell Foster when he was an engineer at Mooney many years ago: CD = 0.164 + 0.72CL2 A more fun way to determine the optimum parameters for your airplane though is to just do a bunch of flight testing.

Somehow I lost 1 of my hub caps on a long flight I did recently on my - new to me - M20J. I think I may have misaligned the screws when I inspected and one day the left one was just not there after I landed. So, I am trying to buy just one of them since they're ~ $300 new for a pair. Does anyone have one of them available? If anyone is on the same boat we could split a new pair as well .

I have the LoPresti Cowl on my M20J and it is difficult by myself but easy with a helper. Not really much difference between the 2 and 3 blade prop in this regard.

Keep in mind the original poster @Speed Merchant (Curt LoPresti) is looking for the "best carpet kit" for his 201. He already tried a local shop that couldn't do it to his satisfaction (no surging machine for the edges). He's not looking for auto carpeting. He hasn't skimped on anything so far in renewing this M20J 201. Not only is this his personal airplane, but I'm guessing it's a bit of a tribute to his father Roy LoPresti (father of the M20J 201). https://en.wikipedia.org/wiki/Roy_LoPresti

paint itself typically does not cause any measurable speed increase, however a lot of people add speed mods before doing paint, like e.g. flap gap seals, aileron gap seals, in the extreme a Lopresti cowl, scimitar propeller, doing all the above you may be able to squeeze another 6-8 knots out of a J at considerable expense, best bang for the buck are the flap gap seals producing 1-2 kt

On my J have the LoPresti cowl and have an inspection door on both sides that spans the baffling so I can see both in front and behind the baffling at pre-flight. It really helps but there is still just so much you can see. I find I can remove and replace the top cowling by myself with little trouble but I don't recall if it was like that with the original cowling.

It has been discussed many times here. The issue with PowerFlow on the J models is that the induction and exhaust system on the on M20J is really well optimized ("tumed" as you refer to it) in its stock form. Whether it was luck or good slide rule/LoPresti common sense engineering of the J, the gains to be rung out over the stock design are minimal. In 2020, @PT20J highlighted that the PowerFlow rep was at MooneyMax and admitted so much. Other owners like Wistarmo (who is no longer on MS) reported no improvement when bolting it onto a 1993 MSE. PowerFlow, founded in 1997, has been putzing around with this for nearly 30 years. If they can't find more power for the J, either through flow studies/testing, engineering or just plain trial and error, I doubt anyone will. They were first working on this when the J was still in production. Certainly no one else will waste time and money for a shrinking fleet. On the other hand, the PowerFlow has been reported to deliver some benefit to pre-J's because of their sub-optimal plumbing.

I had a G- model in the late 90s, flying restoration, stock about 137 KT TAS, with alle mods available at the time it went to 155 KT, today there is the Lopresti cowl which gives you another 5 KT, however all that stuff in combination is expensive and time consuming to install, better all bought together installed already . The most bang for the buck is delivered by flap gap seals, aileron gap seals and elevator and rudder hinge covers, all sold by Lasar, a honest 3kt, weight maybe 1lb, after that comes a cowl closure, maybe another 2 kt, once you start, hard to draw the line where to stop, enjoy the journey!

Sort of . . . but not really. In 1983 the 301 was a Roy LoPresti concept of a piston pressurized single to compete with the Piper PA46. Due to lack of capital the project was scrapped but the idea of a single engine pressurized turbine, instead of piston, came out of that. in '85 Mooney was bought by a French company that bought Socata the same year. In '87 a clean-sheet design project started on the TBM 700. Nothing carried over from the 301 to the TBM 700 except the concept of a single engine pressurized turbine. For Mooney's part they were supposed to build the wing in Kerrville to provide steady work for the factory, which never happened. But yes "M" in TBM is for Mooney and TB is for Tarbes, the city in France where they ended up being built

I think you just got a bad Concorde. They usually last much longer. It may have been discharged all the way down once during its life which is hard on the battery or maybe sat in the shelf awhile before you bought it. Next time you're at an air show where Concorde has a booth I would walk up and introduce yourself (the name LoPresti still carries a lot of weight ) and let them know "what great success you've had with their batteries and how you've always recommended them . . . except for this last one. Are they not made as well as they once were? I'd like to be able to recommend them to pilots I know, but . . " They are a good company and I bet they do something for you, a Visa gift card which they sometimes give at airshows. They want to know.

I think people get to love what they become familiar with. I think the F has a lot going for it. Is it because I own one? Well yes. It is hard to really understand what's great about an airplane until you've lived with it a while. What I think is superior about it compared to other 4 place singles: Light weight (<1700lbs) Manual gear and flaps. Retractable step (continues to function flawlessly after 57 years with no mx, just lube) Good speed (reliable yields 150kt cruise over a broad range of altitudes) Solid climber into the teens (easily avg 1000fpm to 10,000' when solo) Fun to yank and bank at light weights Good short field performance. Stable cross country platform Enough UL to put 800lbs in the cabin and go 500NM with reserves Bendix S20/200 mags Excellent heating and ventilation system. Comfortable for four adults. Folding, split rear seats. I like the smooth flight controls on the vintage birds Good access to back side of instrument panel What I think is suboptimal: Cowl shape Cowl aesthetics Steeper windshield angle. ( though I actually like the look of the two piece) Twist wing (only because wing tips are not available) No gross weight increase available (if there were, I'd have a UL of 1,219lbs making it one of the best load hauling piston singles in existence) What I would do to make it better if money were no object Perhaps a TN system slope windshield mod 201 or Lopresti cowl mod There are panel and interior upgrades galore. These are more a reflection of the owner's tastes and budget than a model specific attribute.

The time has come - I finally found my Turbo/FIKI Mooney to upgrade to, so I must list our first child, Rojito "Jito" ... I hope to find a good caretaker for him here rather than posting to Controller or elsewhere. I've taken meticulous care of it and have had very clean annuals. We've been across the country multiple times and it's as good of a cross country J as any out there - trues at 155-160 ROP of 145-150 LOP depending on OAT/conditions. I love that it has the modern Mooney interior with split removable rear seats to extend storage space (how I flew it most of the time). I also was drawn to it originally due to the centri-lube cam STC that was added before my ownership ... helps keep the camshaft/lifters oiled at all times. I've upgraded the panel a bit with a new GTN750 & PMA450B to go along with the Aspen & STEC-55x, but it still has redundant steam gages as well for peace of mind in IFR flying. 1977 Mooney M20J N201NG Serial #24-0253 Price: $140,000 USD Airframe: 6262 TT (flown actively so times will change) Engine: 832 SMOH – Lycoming IO-360-A3B6D (Major overhaul to new limits 8/2003, IRAN 6/2008) Propeller: 510 SNEW – McCauley BlackMac B3D36C424/74SA-0 (Factory new 9/2008) Max Gross Takeoff Weight: 2740 pounds Basic Empty Weight: 1844 pounds Useful Load: 896 pounds Usable Fuel Capacity: 54 gallons Empty CG: 46.659 inches General: · Aircraft located at Sporty’s Clermont County Airport (I69) · LoPresti Super201 Cowling & Speed Mods (step removed) · Always US-based · Annual inspection due 2/2023 · IFR certification due 2/2023 · ELT battery due 12/2025 · All FAA AD’s in compliance · 2/2022 compressions were 72/74/70/69 · GAMI Injectors – runs deep LOP without issue, 0.1-0.2gph GAMI spread · Firewall Forward Centri-Lube Cam STC installed – introduces continuous flow of oil between camshaft and lifters to reduce friction/temperatures and extend engine life · Blackstone oil analysis history available … no anomalies Avionics: · Aspen EFD 1000 Pro PFD (with SVT, AOA, & STEC-55x Integration/Altitude Pre-Select/GPSS) · Garmin GTN 750 #1 WAAS GPS/NAV/COM · Garmin Flight Stream 510 · Garmin GDL69A SiriusXM Weather & Radio Receiver · Garmin SL30 #2 NAV/COM · STEC-55x Autopilot with Electric Trim · Garmin GTX 345 ADS-B in/out transponder (displays ADS-B traffic and weather) · JPI EDM 830 color engine management system · PS Engineering PMA450B audio panel – 2x Bluetooth antennas · Garmin CDI slaved to NAV2 · Davtron digital chronometer · Back-up airspeed indicator, turn coordinator, altimeter, vertical speed indicator, attitude indicator, and heading indicator · Ameri-King AK-450 ELT Additional Equipment: · LED Nav Lights & Rear Position Light · LoPresti Boom Beam Landing Light – much brighter than LED · Whelen strobe · Sun visors · Tinted rear windows · Working ram air system – adds ~1.5-2” MP at altitude · Precise Flight SVS standby vacuum pump system · David Clark powered headset modules for pilot/copilot · BatteryMINDer 12v system included with sale – quick connect kit installed with access through ground power door on tail of fuselage · Tanis engine pre-heat system · Cowl plugs & pitot tube cover included with sale · Bruce’s Custom Cover for aircraft fuselage included with sale · O&N Fuel Tank Bladders – no more leaking tanks, can add one more cell to get back to 64 gallons (Griggs Aircraft) Miscellaneous Maintenance: · New oil cooler 1/2022 · Muffler overhaul 1/2021 · New spark plugs 1/2021 · New left main tire 10/2020 · New wing walk painted & paint restored/waxed 8/2020 · New Donaldson air filter 6/2020 · New intake pipe for Cylinder #2 3/2020 · New main gear shock discs 3/2020 · Battery box cleaned/painted 3/2020 · Rigging of all control services reset to factory spec by MSC 3/2020 · Gear travel, trusses, bushings, and hardware serviced & adjusted to spec by MSC 3/2020 · New brake linings 12/2019 · New Concord battery 9/2017 · Overhauled fuel boost pump 2/2017 · Prop Strike 3/2008 – sent to Firewall Forward for IRAN & new prop installed Exterior: · Fuselage/Tail re-painted 6/2007 · Painted by Mena Aircraft Painting 5/2004 – 7/10 condition · Matterhorn White with Red Baron and Outer Space Gray Trim Interior: · Full modern Mooney interior installed at Mooney factory 3/2007 · Grey leather interior with grey carpet – 9/10 condition · Split, removable rear seats – opens up tons of storage room (not a Mooney option until ~85 model years and later) · Modern plastic side panels replace older style · 3-point inertia wheel seat belts for pilot and co-pilot

Anyone here with an E or F model done the Lopresti cowl mod Thanks, Michael

Where did you see the cost? Is there a TBO on these yet? 235hp on a supercharged motor would be a pretty solid performance mod on a M20J. Basically no hp loss at 8k and would cruise 180 kts on 10.2gph. I wouldn't be surprised if these were the numbers. If people think about stuff like lopresti mods and what not, that cost 20g's to gain 5 kts.... I think this would be worth the weight trade off. Which shouldn't be much anyway.

I installed the very first Deltahawk diesel on N1974B, the test bed Cirrus SR20, at LoPresti's Sebastian facility in 2013. The engine itself is simple, robust, and well though out. Deltahawk has spent a decade refining the design, and I would take it any day over any other diesel on the market.

Well that plus reduce weight, complexity by a lot plus move the bottom cowl way up because it doesn’t have to house a nose wheel, there by significantly reducing drag by quite a bit. LoPresti's Fury as an example, pretty sure it had a 200 HP Lycoming angle valve, but I believe he had the 540 in mind. Of course we won’t likely ever see anymore Mooney’s period, much less a taildragger, but I’d like one. This is all just dreaming.

I think unconventional I outgrew tricycles when I was three or four maybe. I think a Mooney would be a perfect T/W. Less complex, lighter weight, faster due to smaller frontal area, and most important to me lots more leg room without that nose wheel well right in the center of the floor, and I think it would be easier to get into and out of with the trailing edge of the wing lower to the ground, more prop clearance making prop strikes less likely and less wear from rocks and sand. Might could even run a longer prop and be more efficient, even faster still. I think LoPresti was onto something with his Fury, would have been much better / faster if it had been an M20 though with the Laminar flow wing etc. Only draw back I see is it would require greater pilot proficiency.

Long time ago, all available mods besides a Lopresti cowl which was developed later

I've had a D-3000 on my M20J for the 28 years Ive owned it and other than 500 hr inspections have never had a single issue with it. In addition to using a shop that knows how to properly install it with new hold down hardware, I put a witness mark across the nut and check it during preflight (though I have a LoPresti cowling so I can inspect that through the left side access panel).

The lowest drag would be with the elevator aligned with the stabilizer and it seems that the original design does that. When the fuselage was lengthened it threw things off. My J, for instance trims with the elevator slightly trailing edge down. A Mooney engineer once told me that Lopresti calculated that it didn’t make enough difference to bother fixing which would have required an expensive redesign of the empennage to change the incidence of the stabilizer. Lengthening the fuselage again and changing the trim system resulted in the long bodies trimming with the elevator slightly trailing edge UP. The purpose of any trim system is to remove stick force. This can be done by changing the incidence of the horizontal stabilizer, using a trim tab to bias the elevator, or using springs. The tab by itself is powerful enough because it taps into aerodynamic force. Springs alone can be troublesome because springs strong enough for cruise speed are too strong at low speeds and make the controls too heavy for landing. Changing the stabilizer incidence may require too much trim wheel rotation with the gearing necessary to make the trim wheel easy to turn. So, it is not uncommon to use a combination of springs and variable incidence. I believe the Piper Cub does that also. Skip

Hi everyone Finally got N201JX airborne today after way too long, with a new Aspen display, EDM-930 engine display and some other goodies. Took out a bunch of old stuff too and our corrected empty weight (including oil but not unusable fuel ~15lb) is 1750#. I am now FINALLY able to get some much higher fidelity data off this airplane. One of the first things I wanted to check is the max level flight effectiveness of the Lopresti SCRAM (super clean ram air mod) at full power and low altitude. Here is the plot: Bottom line is a 1.3" manifold pressure increase. The hp from Benchmark is 173hp before, and 182hp after. Of course there is a commensurate increase in fuel flow as shown by the blue line. This is an interesting exercise for air racing perhaps, but the real use would be at medium altitude once a full WOT LOP cruise is set up. That will take me a little longer, first indications are a GAMI spread of 1.0 GPH with cylinder 1 being much richer than the others (last to peak). This is at 8500', WOT and 2500 RPM and a little colder than standard day. The normal air filter intake is a little lossy, I only have 21.4" under these conditions. About 8.6 gph LOP but #1 is barely over the peak and #3 is 50 deg lean, and is on a pretty steep negative power slope at this point....meaning ham-fisted leaning might proceed to a rough engine and a nervous pilot. Can't have that. Note here also the SCRAM add on the top yellow MAP line after LOP, from 21.4 to 22.2 inches MAP, increase of .8" and roughly 5 hp. Again a commensurate increase in FF on the blue line, but I did not touch the mixture and the EGTs basically remained constant. Most M20Js are ~155 to 157 KTAS under these conditions. N201JX is nicely faster than this, but I had only one on board and half fuel so pretty light. It's not going 180 KTAS guys, need a turbo or cubic inches for that. More data later. I am thrilled to have this airplane airborne again, finally.