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Vintage Mooney Cowling Mod


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Hi Mike, looking forward to the Summitt and meeting you. Thanks for all your generosity.

Carusoam, I was really hoping to have some performance numbers by Osh to share with everyone who is interested, but delays in getting parts kept me from completing it. I'll show anyone who's interested in seeing the main parts what they look like and listen to any suggestions offered to improve my project.

Thanks,

David

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Looks very good.

What about a piece of clear plexiglass or acrylic as a lense to cover the landing light opening? ... molded or shaped to fit behind the cowl opening but in front of the landing light assembly ... use screws (or slightly longer screws) to replace the rivets that attach the landing light assembly?

Would that possibly give it another knot or two?

.

Not sure about the heat from a normal bulb? If it would melt or distort a lens placed in front of it? I guess you'd need to be picky about the material used?

We did Aero Resources Inc. Landing Light Lens mod which does this ... and put in an Parmethius LED bulb at the same time - so never worried about heat or leaving it on a long time ...

Lasar has molded covers. 

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Hi David,

I do plan on incorporating a lens for the landing light. I had one on mine for the last four years and it had a little distortion from heat. It fits between the cowling and landing light housing. I'm planning on having it cut around the edge where it will be flush with the cowling. I haven't made the new one for mine yet.

Thank you,

David

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All the questions asked thus far could be compiled into a faq. For example: do I need a 337, is it a stc, which model years are covered, is there any weight change, will it increase cooling, how long to install it, does it make doing pre flights easier, when will it be ready.

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Sabremech showed up at the Mooneyspace get together today and showed off the work.  We talked about how it works for a C (such as his own) and the potential for using on an E model (like mine).  Sounds pretty good in that the cowl inlet holes are really good for cooling.  Here are some of the considerations.

 

First, the new cowl does not have the bump at the top such as on mine and any Mooney manufactured in 1965.  David says he might have to do some magic in the design of the top cowl for us in that year.

 

Second, there is no ram air vent (too much trouble in moulding and getting FAA approval for the STC).  However, the relocated air filter (below the port inlet and in front of No 2 Cylinder) will apparently allow for an increase by about 1" in manifold pressure, without the need for the ram air (enhancing the not-very-good air intake system on our Lycomings).

 

Fourth - the doghouse is gone.  This concerns me a little because I now get no more than 350-360 deg F as CHT on the very hottest departures because of the efficient cooling of my current doghouse.  If I am to now make use of a J-type baffling system, I want it to be very good too.

 

Lastly, I will need the J spinner because this new cowling is a bit further forward than my current one.

 

I want one, but Clarence is my expert and we will need to talk.

 

Well done David (Sabermech).  Very good looking result of your work.  We are pulling for you, because it will affect us too (hopefully).

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Hi Ned

It was great meeting you and more Mooneyspace members. I appreciate the comments and feedback. I have a ways to go but I think I'll have a good product with good enhancements to cooling, speed and aesthetics.

I'm here until Saturday and would like Clarence to see the parts and get his thoughts on the project. Give me a call or send me a text at 847-227-7008 and I'll meet with you guys.

Thank you,

David Staffeldt

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David and Ned- very nice to have met both of you by the Mooney Caravan tent.

The cowling mod is very impressive. I'm really looking forward to seeing the results in terms of CHTs and airspeed gains over your previous ARI cowl mod.

Very well thought out. Simple, but elegant, solutions to problem areas and challenges. Any of our members who are mechanical or fluid engineers will agree, I'm sure, especially after hearing your rationale behind them.

Nicely done, and thanks for bringing it to Oshkosh.

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Sabremech showed up at the Mooneyspace get together today and showed off the work.  We talked about how it works for a C (such as his own) and the potential for using on an E model (like mine).  Sounds pretty good in that the cowl inlet holes are really good for cooling.  Here are some of the considerations.

 

First, the new cowl does not have the bump at the top such as on mine and any Mooney manufactured in 1965.  David says he might have to do some magic in the design of the top cowl for us in that year.

 

Second, there is no ram air vent (too much trouble in moulding and getting FAA approval for the STC).  However, the relocated air filter (below the port inlet and in front of No 2 Cylinder) will apparently allow for an increase by about 1" in manifold pressure, without the need for the ram air (enhancing the not-very-good air intake system on our Lycomings).

 

Fourth - the doghouse is gone.  This concerns me a little because I now get no more than 350-360 deg F as CHT on the very hottest departures because of the efficient cooling of my current doghouse.  If I am to now make use of a J-type baffling system, I want it to be very good too.

 

Lastly, I will need the J spinner because this new cowling is a bit further forward than my current one.

 

I want one, but Clarence is my expert and we will need to talk.

 

Well done David (Sabermech).  Very good looking result of your work.  We are pulling for you, because it will affect us too (hopefully).

 

As an F pilot I don't really see the need for the Ram air.  I used it once when I first got the plane, have not touched it since.  If I am high enough to open it, I am also running lean to minimize fuel burn.  I have no need for more MP then.  A better air filter with higher MP on take-off would be a big advatage here in the west at high DA.   I would not miss it if it was gone and Mooney realized the same thing and removed it later in the J.  We can save a few pounds and remove all the hardware from inside the cowl.

 

I do wish there was a way to not have to change the spinner.  This will add about $2000 to the cost of the project.

 

Thanks for all the hard work David.

 

Tim

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As an F pilot I don't really see the need for the Ram air. I used it once when I first got the plane, have not touched it since. If I am high enough to open it, I am also running lean to minimize fuel burn. I have no need for more MP then. A better air filter with higher MP on take-off would be a big advatage here in the west at high DA. I would not miss it if it was gone and Mooney realized the same thing and removed it later in the J. We can save a few pounds and remove all the hardware from inside the cowl.

I do wish there was a way to not have to change the spinner. This will add about $2000 to the cost of the project.

Thanks for all the hard work David.

Tim

Tim -- curious how much MP gain you saw. I am seeing 1.5". If I recall correctly, the big difference between our F and the J ram intake is that our ram door opens directly to the throat of the intake and the J's has a big bend in it. They see a lot less increase.

My biggest issue with the F ram system is the rubber? boot that seams to be wearing out again.

Sent from my iPad using Tapatalk

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Tim -- curious how much MP gain you saw. I am seeing 1.5". If I recall correctly, the big difference between our F and the J ram intake is that our ram door opens directly to the throat of the intake and the J's has a big bend in it. They see a lot less increase.

My biggest issue with the F ram system is the rubber? boot that seams to be wearing out again.

Sent from my iPad using Tapatalk

 

 

me too.. you mean the bellows behind the door, right?   I haven't used my ram air yet just because the rubber boot looks so old, tired, and brittle... Where can these be bought, and how much?  

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me too.. you mean the bellows behind the door, right?   I haven't used my ram air yet just because the rubber boot looks so old, tired, and brittle... Where can these be bought, and how much?  

from your favorite MSC. They are one of the Mooney "margin makers" however. Last time I bought one it was north of 400.

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from your favorite MSC. They are one of the Mooney "margin makers" however. Last time I bought one it was north of 400.

 

yikes... so, does this cowl mod retain the use of that rubber bellows?  Sure would be nice to save the cost of replacing that part if one were to buy the cowl.. 

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Chris,

 

I saw about 1.5" at 7,000 feet.  Unless I have really screwed up and need to get 5 knots faster plus about 2-3 gallons more per hour burn rate I don't see a need for it.  I fly at 9 to 12K msl most of the time and pull the fuel flow back to 9 gph.  One more system to maintain and my mechanic really loves it when we have to pull the bottom cowl off, not.  I would be glad to have a better induction system and no ram air.  My goal is 150 knots TAS at 9 gph, right now I'm at 139 knots with a mostly stock F.  I would like 201 windshield, new cowl, and inner gear doors, poor man's J.

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Chris, I get 1"+ MAP boost. ('66E with PFS.)

Chris,

I saw about 1.5" at 7,000 feet. Unless I have really screwed up and need to get 5 knots faster plus about 2-3 gallons more per hour burn rate I don't see a need for it. I fly at 9 to 12K msl most of the time and pull the fuel flow back to 9 gph. One more system to maintain and my mechanic really loves it when we have to pull the bottom cowl off, not. I would be glad to have a better induction system and no ram air. My goal is 150 knots TAS at 9 gph, right now I'm at 139 knots with a mostly stock F. I would like 201 windshield, new cowl, and inner gear doors, poor man's J.

We're in the same range. I don't use it much, but I'm one of those J wannabes :).

Come to think of it, I never opened up the ram air when I was being challenged by Stinky Pants in our infamous F vs. J battle. I was kicking his butt with "filtered" air. Gotta remember that the next time I post some speeds for him.

As for speed. I have a modded F (201 windshield, cowl enclosure, aileron & flap seals). I flight plan 150 KTAS at 10 GPH, but usually am around 9.8 or a little less (ROP).

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Thanks guys for all of the comments and questions. I've researched the ram air on the E & F models and talked with some very knowledgeable Mooney folks and the consensus is that by moving the filtered air into the left cylinder air inlet, the same boost to mp can be achieved. if I do this, I can use most of the same parts except for the air inlet for the fuel injection on the 66 C, E, F & G models. This will keep the costs down if I can do this under one STC. It will do away with all the ram air rubber seals and the air filter on the above models and make them more in line with the J model. I'd like to find an option for the spinner, but if it's not already certified and fits certain dimensions, it can add 100 hours of test flights to get it certified as part of the STC. That would delay the project and raise costs, so it's a matter of where's a good balance in the cost vs benefit in the project.

It was great meeting and talking with Ned, Clarence, Yves, Andy, Johnathon, Vincent and many more.

Thanks again,

David

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David, on my '66E I have a Fiberglass nose cowl by AeroResources Inc  STC SA7589SW and a Mooney 201 M20J Spinner & spinner bulkhead assys from Aero Resources Inc STC SA7589SW. 

 

That was from 1997. I now have a Scimitar Top Prop and the long pointed spinner.

 

I wonder if my spinner/prop would take new cowl? 

 

We'll hope to see you at Mooney Summit!

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Sabremech showed up at the Mooneyspace get together today and showed off the work.  We talked about how it works for a C (such as his own) and the potential for using on an E model (like mine).  Sounds pretty good in that the cowl inlet holes are really good for cooling.  Here are some of the considerations.

 

First, the new cowl does not have the bump at the top such as on mine and any Mooney manufactured in 1965.  David says he might have to do some magic in the design of the top cowl for us in that year.

 

Second, there is no ram air vent (too much trouble in moulding and getting FAA approval for the STC).  However, the relocated air filter (below the port inlet and in front of No 2 Cylinder) will apparently allow for an increase by about 1" in manifold pressure, without the need for the ram air (enhancing the not-very-good air intake system on our Lycomings).

 

Fourth - the doghouse is gone.  This concerns me a little because I now get no more than 350-360 deg F as CHT on the very hottest departures because of the efficient cooling of my current doghouse.  If I am to now make use of a J-type baffling system, I want it to be very good too.

 

Lastly, I will need the J spinner because this new cowling is a bit further forward than my current one.

 

I want one, but Clarence is my expert and we will need to talk.

 

Well done David (Sabermech).  Very good looking result of your work.  We are pulling for you, because it will affect us too (hopefully).

My 67 did not come with a dog house and it runs as cool or cooler than the numbers that you've quoted.  As long as the design gets airflow to the right places in adequate quantity, it should be no problem!

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