Still thinking about an RV-14

Need to put Jim on retainer for finding deals when it's time to start my build.

The Lycoming suffixes and what can be converted can make ones eyes water.
 
You sure that engine from the twin turns the prop the right direction? :p
 
Better yet, put the seats in backwards...bam!... pusher canard. Just call me Burt.
 
flyingcheesehead said:
Hah... That was enough information for me to correctly guess what you were talking about:

en.wikipedia.org

Partenavia P.68 - Wikipedia

en.wikipedia.org en.wikipedia.org
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I saw the video of the plane ripping its outer wing sections some years ago.

September 11, 1983: A P.68C, N29561, performing an aerobatic display broke up in flight during an airshow in Plainview, Texas. The NTSB report revealed that analysis of the video showed the aircraft performed a fly-by over the runway, exceeding its Vne (Velocity, never-exceed) speed by 27 knots. The pilot then executed a sharp nose-up pitch change of about 8 degrees, which spiked the aircraft's dynamic load factor to 8.3Gs and caused both wings to fail in the main spar just outside both engine nacelles then separate from the aircraft, which then began rotating, causing the rear fuselage to twist along its length between its cabin and empennage.
 
AV8R_87 said:
I saw the video of the pilot plane ripping its outer wing sections some years ago.
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FTFY. Wasn't the plane's fault the pilot repeatedly and grossly exceeded the plane's limitations. Sure felt bad for his girlfriend he left behind who was the announcer and watched the whole thing happen, though.
 
Spent the evening inventorying my new engine, which arrived yesterday. I'm very pleased. All the parts were overhauled in 1999, and packed in preservative grease. Everything looks perfect still except the piston pins, which were inexplicably VERY rusty. As I mentioned, no cylinders, but I'm counting that as a feature. Everything is here except the pushrods & tubes, tappets, valve covers, and ball & spring for the oil pressure relief valve. Also no fuel system with the exception of the rotary fuel pump. I'm pretty excited. I'm going to pack everything away and try not to think about it until I have the fuselage nearly complete.

I'll have to send the case out to be cut for 390 cylinders, but I think everything else is ready for assembly. I'll try to sell the turbo sump and dual mag. Not sure if the "cold air" sump is worth it or not over the standard io-360 parts, so I'll have to research that. Also need to find out how many years in advance I need to order the cylinders to get them in time.

It'll be a bit of a puzzle as although everything is bagged up nicely, it either wasn't labeled or the sharpie wore off in the course of the last quarter decade. Thankfully, having been through this once, everything looks pretty familiar. This would be pretty daunting if I was coming into it cold.

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Jim K said:
Spent the evening inventorying my new engine, which arrived yesterday. I'm very pleased. All the parts were overhauled in 1999, and packed in preservative grease. Everything looks perfect still except the piston pins, which were inexplicably VERY rusty. As I mentioned, no cylinders, but I'm counting that as a feature. Everything is here except the pushrods & tubes, tappets, valve covers, and ball & spring for the oil pressure relief valve. Also no fuel system with the exception of the rotary fuel pump. I'm pretty excited. I'm going to pack everything away and try not to think about it until I have the fuselage nearly complete.

I'll have to send the case out to be cut for 390 cylinders, but I think everything else is ready for assembly. I'll try to sell the turbo sump and dual mag. Not sure if the "cold air" sump is worth it or not over the standard io-360 parts, so I'll have to research that. Also need to find out how many years in advance I need to order the cylinders to get them in time.

It'll be a bit of a puzzle as although everything is bagged up nicely, it either wasn't labeled or the sharpie wore off in the course of the last quarter decade. Thankfully, having been through this once, everything looks pretty familiar. This would be pretty daunting if I was coming into it cold.

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How'd you find this and figure out how to convert to a 390?
 
Racerx said:
How'd you find this and figure out how to convert to a 390?
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It was on ebay of all places. I was trying to find all the models of wide deck, angle valve, front governor io-360's. Looking through the parts manuals, I noticed that the tio-360's (and a few hio's) use the same bearings as the io-390, meaning they use the same heavy crank. Searching for tio's for sale uncovered this one.

I had previously gotten the information from monty barrett (jr.), who is working at divco, that any wide deck 360 case can be modified for 390 cylinders. He said his dad used regular small crank 360's for the first 390's, and they seem to hold up fine, but lycoming decided the extra power justified the heavy crank when they started building them.
 
Forgot to mention, I was surprised to find that aircraft specialties dynamically balanced the crank, and Barrett balanced the rods. Whoever was working on this 25 years ago was doing it right. AS also traded him out the turbo cam for a regular io-360 cam, so there's another part I won't have to buy.
 
Just got off the phone with Lycoming support. How cool is it that they will pick up the phone and answer your questions?

The IO-390 specifies 77450 connecting rods. I have LW-13422 rods. They both start as the same LW-13756 casting. Same bushing, same bearing, same dimensions. The only difference so far as we can see is that the 77450 uses the 75060 bolts, while the 13756 uses the more expensive LW-12596 with thicker heads, same as my 540. We thought maybe it was a clearance issue with the bigger 390 cylinders, but the IO-580 uses the thicker headed bolts as well :dunno: so it seems like somebody just made an arbitrary choice. The 13422's are approved to use the 75060 bolts as well, so that's what I'll probably do. Confused yet?

The tech support guy was curious and asked what I was up to, so I came clean. He was familiar with the C1A6D and the Partenavia from whence it came. I explained my plan, and he said..."yeah, that should work", which gave me the warm fuzzies. No shade at all about kitbashing an experimental motor together to avoid handing them $70K. Pretty cool.
 
Thats very encouraging. Isnt it nice to put it together with the parts you can find AND want, without playing "mother may I?" with a licensee or designee?
 
Jim K said:
Just got off the phone with Lycoming support. How cool is it that they will pick up the phone and answer your questions?

The IO-390 specifies 77450 connecting rods. I have LW-13422 rods. They both start as the same LW-13756 casting. Same bushing, same bearing, same dimensions. The only difference so far as we can see is that the 77450 uses the 75060 bolts, while the 13756 uses the more expensive LW-12596 with thicker heads, same as my 540. We thought maybe it was a clearance issue with the bigger 390 cylinders, but the IO-580 uses the thicker headed bolts as well :dunno: so it seems like somebody just made an arbitrary choice. The 13422's are approved to use the 75060 bolts as well, so that's what I'll probably do. Confused yet?

The tech support guy was curious and asked what I was up to, so I came clean. He was familiar with the C1A6D and the Partenavia from whence it came. I explained my plan, and he said..."yeah, that should work", which gave me the warm fuzzies. No shade at all about kitbashing an experimental motor together to avoid handing them $70K. Pretty cool.
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This does not sound like this:

“I'm going to pack everything away and try not to think about it until I have the fuselage nearly complete.”

:)
 
So. Is this the “big engine” for an RV 14? Or the non acrobatic “normal” HP engine?
 
Dave Theisen said:
This does not sound like this:

“I'm going to pack everything away and try not to think about it until I have the fuselage nearly complete.”

:)
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:dunno: did anyone really believe that? :biggrin:

WDD said:
So. Is this the “big engine” for an RV 14? Or the non acrobatic “normal” HP engine?
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The -14 was designed around a 210HP IO-390. Since then they've come up with an improved version of the 390 at 215HP and also installed a 200HP IO-360 in the TW demonstrator. This build should be very close to the 210HP version. I'm hoping that with a good exhaust and possibly a cold air intake, I might be able to beat that. My plan would be to have this thing run in & dyno'd before it goes on the plane. I'm not going to do inverted fuel or oil on this one.
 
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Jim K said:
The tech support guy was curious and asked what I was up to, so I came clean. He was familiar with the C1A6D and the Partenavia from whence it came. I explained my plan, and he said..."yeah, that should work", which gave me the warm fuzzies. No shade at all about kitbashing an experimental motor together to avoid handing them $70K. Pretty cool.
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I've found a lot of guys like this really enjoy hearing what cool things end users do that's outside the norm.
 
Any change needed to the intake manifold and exhaust system, given your larger displacement? Or do our aircraft engines not use intake and exhaust tuning / pressure wave scavenging what not?

From my old motorcycle days, guys would proudly get rid of their air box and put on individual pods, as well replace their exhaust system. While louder, they couldn’t figure out why they lost power.
 
WDD said:
Any change needed to the intake manifold and exhaust system, given your larger displacement? Or do our aircraft engines not use intake and exhaust tuning / pressure wave scavenging what not?

From my old motorcycle days, guys would proudly get rid of their air box and put on individual pods, as well replace their exhaust system. While louder, they couldn’t figure out why they lost power.
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Some engines are more tuned than others. My 540 had a tuned length intake (or appeared to). The IO-360 sump is not very efficient. The 215hp 390 uses a "cold air" intake that looks like it had a little thought put into it. I don't think there's too many gains to be made at these kind of engine speeds. Some exhausts seem to be worth 5hp or so.

I think the problem with cars & bikes is that people make them breath better without adjusting the fueling, making them run lean. Much less of a problem when you have a mixture knob.
 
The 4 stroke motorcycle guys are usually unaware that scavenging even exists, but the 2 stoke guys have exhausts that looks like they were made by Dr Seuss.
 
I propose a title change. You are no longer thinking. You are building. This should, by all rights, be "Still Building an RV-14."
 
Been out of the field for a couple days due to rain, so I've been working on the fiberglass. The tail kit is now done. Just finished with a visit from our chapter's tech counselor, who said that it looks like "very good workmanship" and didn't finds any faults with it. Next step is to take it back apart and stash it to make space to build the wings. My estimated ship date for the wing kit was supposed to be 5/1, but I haven't heard anything yet. Hopefully they don't make me wait too long.

OTOH, I should probably work on some of those house projects...

IMG_20250504_195755054_HDR.jpg
 
Skyrys62 said:
I'm imagining you walking around the shop with that old phone squished between your ear and shoulder saying "hang on, Imma rivet this real quick"..
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My Dad did away with the landline....10? years ago. I thought about taking it off the wall when I cleaned the shop out to start this project, but I decided it was historical enough to leave it. I hung it there in high school and the numbers written on the wall in sharpie include two long-closed motorcycle shops and my college best friend (both cell and milking barn :D). And yes, it has a real long cord that reaches clear across the shop.
 
Mmm... Sexy airplane parts

Superior cold air intake. Looks like I might have to file a couple of the holes a bit, but otherwise pretty great. Kit comes remarkably complete. Hardware, gaskets, intake tubes, silicone couplers, hose clamps all included. IMG_20250509_082337544.jpgIMG_20250509_082343053_HDR.jpg
 
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Racerx said:
8' beds are the only way to go!

Lemme know if you want us to build a mezzanine above tail of the Lance to keep things tidy
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I wish you'd build me a bifold door...
 
Doesn't this RV 14 deserve its own hangar? (Hey, easy to suggest when it's not my money :biggrin:)
 
Jim K said:
I wish you'd build me a bifold door...
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Was thinking of making my own schweiss style door for the building to build my rv10/14/15. Easier than all the pulleys on the bi-folds.
 
WDD said:
Doesn't this RV 14 deserve its own hangar? (Hey, easy to suggest when it's not my money :biggrin:)
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Not until the wings are ready to get bolted on. Last I checked, the waiting list for the old, small hangars is only 1 or 2, so it shouldn't be an issue to get one when I'm closer to needing it. Either that or get @Racerx to build me a plane lift.
 
Wing kit finally got loaded on the truck yesterday. Estimated delivery date is 5-27. Shop is cleaned out. Might run to the hardware store today for some muriatic acid to try & strip the chrome off those valve covers. If the kit actually takes that long, I might learn how to nickel plate...
 
Jim K said:
Wing kit finally got loaded on the truck yesterday. Estimated delivery date is 5-27. Shop is cleaned out. Might run to the hardware store today for some muriatic acid to try & strip the chrome off those valve covers. If the kit actually takes that long, I might learn how to nickel plate...
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That's what we come to expect! The awe hell I'll do it myself attitude.

If they taught crap like that in science class, I might not have slept.

Another neat science trick is aluminum die grinder burrs with aluminum embedded on them. Toss them in with some lye. Good as new.
 
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