Lycoming IO-390 Question

JC150

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JC150
I heard the Mooney M20 E,F,J, and Cessna 177RG received an STC for the IO-390 back in 2009.

I keep hearing talk about an IO-390 STC being "proposed" for the Arrow... Does anyone know if this is true or just another myth? I'd like to see an IO-390 in my arrow since the engine is coming up on TBO...
 
I heard the Mooney M20 E,F,J, and Cessna 177RG received an STC for the IO-390 back in 2009.

I keep hearing talk about an IO-390 STC being "proposed" for the Arrow... Does anyone know if this is true or just another myth? I'd like to see an IO-390 in my arrow since the engine is coming up on TBO...

From what I've read at Mooney Space, the IO-390 doesn't give you that much of an upgrade from the IO-360 for the extra expense. There are a few 390s out there but not many.

What's weird is that RW numbers on the STC'd Mooney's with the 390s aren't that impressive but looking at the factory installed 390s on the new SR20's the performance difference is significant. (at least on paper, why AvWeb or Flying hasn't done a feature on the SR20 yet, I don't know) I'd be curious why the IO-390 is such a big upgrade on the SR20 and not on a Mooney...
 
that extra HP really helps pull that chute through the wind. :D
 
I'm really interested to see how this will impact the Pipistrel Panthera since they originally proposed using the IO-390 but went away from it since at the time it was delayed in certification for MOGAS.
 
I heard the Mooney M20 E,F,J, and Cessna 177RG received an STC for the IO-390 back in 2009.

I keep hearing talk about an IO-390 STC being "proposed" for the Arrow... Does anyone know if this is true or just another myth? I'd like to see an IO-390 in my arrow since the engine is coming up on TBO...

Call up Lycoming and see if they'll tell you anything. Lycoming did the STCs you referred to, or at least owned them.
 
Is the 390 parallel valve? Or is it angle valve? Does it make a difference in the 390?
 
Please let us know what you find out - perhaps a one-time STC is possible for the Arrow/IO-390 considering the upgrade isn't even 10% of the rated HP.
 
My understanding is the IO-390 is basically a IO-360 but with cylinders from the IO-580 and has "lycoming roller tappets".

I was talking to someone at the airport today who said he had flown a Commander 112 with an IO-390 STC and he said the noticeable difference was in the climb, not so much the cruise.

I did some research on it and found this: http://www.aerodyme.com/Firewall_Forward/390_Super_Sheet.pdf

From what I've read, the IO-390 215hp in the Cirrus SR-20 G6 increased useful load by 150 lbs and will cost less to operate. I also read on some other forum about an IO-390 for the Cessna 175 increasing cruise speed, but most notably climb performance.

For me personally, being able to climb a little quicker in the summer months would be enough for me to go this route.
 
My understanding is the IO-390 is basically a IO-360 but with cylinders from the IO-580 and has "lycoming roller tappets".

I was talking to someone at the airport today who said he had flown a Commander 112 with an IO-390 STC and he said the noticeable difference was in the climb, not so much the cruise.

I did some research on it and found this: http://www.aerodyme.com/Firewall_Forward/390_Super_Sheet.pdf

From what I've read, the IO-390 215hp in the Cirrus SR-20 G6 increased useful load by 150 lbs and will cost less to operate. I also read on some other forum about an IO-390 for the Cessna 175 increasing cruise speed, but most notably climb performance.

For me personally, being able to climb a little quicker in the summer months would be enough for me to go this route.

Just as long as you are aware that it also comes at a noticeable increase in fuel consumption too from what I've read.
 
The 390 is an angle valve engine. Bigger cylinder heads and subsequently a little more weight. Hemi combustion chamber, better flow, bigger cooling fin area. It's wider than a 360 and is known for cool CHTs and warmer than average oil temps. Pretty much what my EX IO-400 is. Look at available props before you buy into bigger is better. It may be great if you can make more thrust with the power, and that comes from the prop.
 
Ya, the coffee can cylinders don't work so hot in 4 cylinder configurations as the vibration is high. Hard on cowls and anything else that vibrates. There is a reason they historically go to 6 bangers.


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Wish there was a way I could get an IO-550 in the arrow!
 
The 390 is an angle valve engine. Bigger cylinder heads and subsequently a little more weight. Hemi combustion chamber, better flow, bigger cooling fin area. It's wider than a 360 and is known for cool CHTs and warmer than average oil temps. Pretty much what my EX IO-400 is. Look at available props before you buy into bigger is better. It may be great if you can make more thrust with the power, and that comes from the prop.

It can't be that much wider if it fits into a Mooney without modification.
 
Have you done one? How it fits would be a good topic. Probably less of an issue on a wider airplane than on a narrower airplane like a Cub. I had to start with a wider nose bowl but the bigger problem was how to fit a second oil cooler. I'd appreciate pireps from guys who've used this motor and especially guys who've upgraded to it.
 
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Just as long as you are aware that it also comes at a noticeable increase in fuel consumption too from what I've read.

I read on the mooney forum it was 0.5gph more in cruise

I was doing some more research and another mooney owner noted a 150fpm increase in climb and a 5 knot increase in speed.

Ya, the coffee can cylinders don't work so hot in 4 cylinder configurations as the vibration is high. Hard on cowls and anything else that vibrates.

Have you done one? How it fits would be a good topic. Probably less of an issue on a wider airplane than on a narrower airplane like a Cub.

I found an STC for a Piper Super Cub IO-390 with MT Propeller, and they claim less vibrations.

Considering you can get one in a cub i dont know why it'd be difficult to put in something like an arrow.

"Feels like a turbine with the roller tappets and cam and counterweighted crankshaft." http://www.hoaircraft.com/PA-18-IO-390-STC.html
 
My mooney had 180ish hours on a 390 upgrade when I bought it. But I've never flown a mooney without it. So.

One thing I did hear -after- I bought it that would have changed my mind a bit is the price of cylinders. Apparently they're $4k. Each. Anyone confirm?

Other than that, I guess I like it. No way to compare, but I've had instructors comment on the good climb rate we get in August in Alabama, so...
 
I read on the mooney forum it was 0.5gph more in cruise

I was doing some more research and another mooney owner noted a 150fpm increase in climb and a 5 knot increase in speed.





I found an STC for a Piper Super Cub IO-390 with MT Propeller, and they claim less vibrations.

Considering you can get one in a cub i dont know why it'd be difficult to put in something like an arrow.

"Feels like a turbine with the roller tappets and cam and counterweighted crankshaft." http://www.hoaircraft.com/PA-18-IO-390-STC.html


That's a salesmans claim on smoothness. And I don't doubt it at high rpm but in the low 2000s or transitioning though the teens 4 cylinders vibrate. Or when at high MP in low 2000s.


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Plus with no competition for cylinders 4K is a joke. North of 2k is a joke for the IO360 200hp cylinders. No competition, at least not on the certified market.


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A friend is installing a 390 in his Cardinal RG in the next few weeks. I can give a report then. I put a MT 3 bladed prop on a Supercub I just rebuilt and it is very smooth. Don
 

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Yeah.. my last instructor said "Your engine runs like a sewing machine.. smoothest I've been in". But from what I've read on here, a really good prop balance might account for that. And a bad one, "engine vibration" in some cases.
 
Personally I would like the option to upgrade the arrow to an IO-390. A lot of other aircraft have it as an STC so I'm not sure why the arrow wouldn't be a good candidate. I sent Lycoming an email so I hope to hear from them soon.
 
Prepare for sticker shock.

The thing that was attractive to me as a buyer of an airplane with it already done was all of the changes that were required.

It's essentially new stuff, firewall forward. New prop, new starter, new engine, new....

Apparently that was.. $50-60k?

Not sure what would be involved in yours, but I got essentially a brand new engine, prop and accessories, and the previous owner took the $$ hit.
 
Is the 390 parallel valve? Or is it angle valve? Does it make a difference in the 390?

It is angle valve.

My understanding is the IO-390 is basically a IO-360 but with cylinders from the IO-580 and has "lycoming roller tappets".

Roller tappets are not exclusive to the 390. Most engines coming out of the Lycoming factory for over 10 years have been roller tappet engines, and I believe that includes the angle valve IO-360s. That is one of the potential reasons to go with a factory reman instead of a field overhaul for a Lycoming. Send in a flat tappet engine, get back a roller tappet. However, all 390s do have roller tappets.

The difference between the angle valve 360/540 and 390/580 is that the cylinders have a slightly larger bore. The crankcases are also bored to accommodate this. External dimensions are the same.

The 390 and 580 make good options for upgrades, provided that the economics and STC exist to support it. Back when I spent a lot of time running those engines, we were (half) joking about figuring out a way to throw 580s into the Aztec or 310. It would've been a great upgrade as there are many aspects of the Continentals I don't like, but I don't think there's enough of a market to support the STC. More horsepower is more better. If you can get more power, you can always pull the throttle back. You can't go more than full throttle.
 
The response I got back from Lycoming is there were no plans to make the IO-390 for the arrow "at this time".

Dang... i was really hoping they would...
 
The response I got back from Lycoming is there were no plans to make the IO-390 for the arrow "at this time".

Dang... i was really hoping they would...

Engine swap STCs end up being a whole lot of work (read: whole lot of investment dollars), and a lot more work than they used to be. Then you have to decide you're going to sell enough to make it worthwhile. There's a lot of airframe side structural items that need to be determined to be strong enough for what you're doing. The FAA has also gotten more stringent about proving things as acceptable. It's part of why we see change happen at such a slow pace.
 
In most cases I think you are money ahead to sell the airplane and buy a bigger one. The IO390 alone costs more than many Piper Arrows.
 
A friend is installing a 390 in his Cardinal RG in the next few weeks. I can give a report then. I put a MT 3 bladed prop on a Supercub I just rebuilt and it is very smooth. Don

How much is the weight change? The last thing a 177/177RG needs is more weight in the nose.
 
Certainly worth more than my arrow lol. For me, an IO-390 is a pointless upgrade. I need cheaper cylinders [read parallel], not go further into unobtainium land. I much rather have an STC to stick the Cherokee 235 engine on this thing and be done with it. Call it the Pa-28R-235 :D All the benefits of the Comanche with none of the museum mx woes, at non-dakota pricing. What's not to love. Of course, that was going to be my dream with part 23 re-write allowing primary non-commercial, and it all came crashing down.

If I was already a cardinal owner and had by-proxy already accepted the opportunity cost of cracked actuators eating the entire yearly operating budget in a single mx action, I'd just bite the bullet and buy a 182RG.
 
Certainly worth more than my arrow lol. For me, an IO-390 is a pointless upgrade. I need cheaper cylinders [read parallel], not go further into unobtainium land. I much rather have an STC to stick the Cherokee 235 engine on this thing and be done with it. Call it the Pa-28R-235 :D All the benefits of the Comanche with none of the museum mx woes, at non-dakota pricing. What's not to love. Of course, that was going to be my dream with part 23 re-write allowing primary non-commercial, and it all came crashing down.

If I was already a cardinal owner and had by-proxy already accepted the opportunity cost of cracked actuators eating the entire yearly operating budget in a single mx action, I'd just bite the bullet and buy a 182RG.

You should look at the difference in the gears between the 177RG and 182RG, the actuation system on the mains isn't even close to being the same. The 177RG more common complete failure is the rod end bearing on the end of the lone main gear cylinder, which resembles a regular hydraulics cylinder a lot more than the splined piston (for each leg) on the 182RG/172RG/later 210s.

http://www.ebay.com/itm/Actuator-As...ash=item1c7f499e3b:g:ezsAAOSwU-pXp5pF&vxp=mtr

http://www.ebay.com/itm/9882015-2-9...ash=item3d35c52004:g:MtsAAOSwzvlW--Ew&vxp=mtr
 
Certainly worth more than my arrow lol. For me, an IO-390 is a pointless upgrade. I need cheaper cylinders [read parallel], not go further into unobtainium land. I much rather have an STC to stick the Cherokee 235 engine on this thing and be done with it. Call it the Pa-28R-235 :D All the benefits of the Comanche with none of the museum mx woes, at non-dakota pricing. What's not to love. Of course, that was going to be my dream with part 23 re-write allowing primary non-commercial, and it all came crashing down.

Back when I was flying the Archer and liked it a lot, I really wondered why they didn't make the PA-28R-235.
 
What is the service celling on on the arrow vs the 235? pounds per horse difference?


I think all the 235s can burn mogas which is very attractive to me.
 
What is the service celling on on the arrow vs the 235? pounds per horse difference?


I think all the 235s can burn mogas which is very attractive to me.

Service ceiling on stretch arrow with hershey wing 200HP is 15k. post '73 Cherokee 235 with the stretch and hershey wing is 13.9k. 14.5k for midget backseat 235. Taper wing arrows have a 16.2k service ceiling, dakotas 17.5k.

The wing matters as well as the power output and total weight. Apples and apples.
 
Back when I was flying the Archer and liked it a lot, I really wondered why they didn't make the PA-28R-235.

Piper did a couple bonehead moves immediately following the Lock Haven flood imo. Consolidation fever was the immediate reaction. The Comanche was the biggest casualty of course, but in consolidating they wrote off the 182 competition and lumped the mission it with the PA-32, which is way too much hull to be carrying around for a 182 mission. The Arrow was made too narrow in its origin in order to not poach comanche customers, and instead of retooling the PA-28 width or upgaging the engine options on the retract, they just ceded that market it up to Cessna. The rest is history. The Dakotas are relative outliers in the market compared to 182s, whereas that wouldn't be the case if they had made the Arrow a 230-250HP contender.
 
Piper did a couple bonehead moves immediately following the Lock Haven flood imo. Consolidation fever was the immediate reaction. The Comanche was the biggest casualty of course, but in consolidating they wrote off the 182 competition and lumped the mission it with the PA-32, which is way too much hull to be carrying around for a 182 mission. The Arrow was made too narrow in its origin in order to not poach comanche customers, and instead of retooling the PA-28 width or upgaging the engine options on the retract, they just ceded that market it up to Cessna. The rest is history. The Dakotas are relative outliers in the market compared to 182s, whereas that wouldn't be the case if they had made the Arrow a 230-250HP contender.

Don't forget they ditched the Aztec. That was another bad move.
 
Engine swap STCs end up being a whole lot of work (read: whole lot of investment dollars), and a lot more work than they used to be. Then you have to decide you're going to sell enough to make it worthwhile. There's a lot of airframe side structural items that need to be determined to be strong enough for what you're doing. The FAA has also gotten more stringent about proving things as acceptable. It's part of why we see change happen at such a slow pace.

With the number of Arrows around, a person would think that obtaining an STC for the 390 in the Arrow would possibly have made more financial sense than to do it for the Cardinal and Mooney. But honestly, I really don't see why Lycoming even bothered to develop the 390 and 580. For the minimal rated power increases over the previously existing engines and lack of airframes acceptable to put them on it seems like an unnecessary expense to develop and certify those engines.
 
With the number of Arrows around, a person would think that obtaining an STC for the 390 in the Arrow would possibly have made more financial sense than to do it for the Cardinal and Mooney. But honestly, I really don't see why Lycoming even bothered to develop the 390 and 580. For the minimal rated power increases over the previously existing engines and lack of airframes acceptable to put them on it seems like an unnecessary expense to develop and certify those engines.

Part of the goal with those STCs was also to go after particular markets that were heavily PMA'd from an engine perspective (i.e. using aftermarket cylinders, going to 3rd party overhaul shops, etc.) to try to bring money back into the company. So it's not just a raw number of aircraft that they were looking at, it's also what people are doing with those engines at overhaul time. The other consideration was how many of the owners were expected to go with the upgrade, which has to do with the demographics. Undoubtedly there are some fleets that tend to have the types of owners that want their planes tricked out, while there are some fleets that do not feel that way at all. I don't know where the Arrow falls into the market there, but it has angle valve cylinders for which Lycoming is the only source if you need new ones. Also going from 200 to 215 HP has less of a benefit than 180 to 215 HP, which was typically the jump they were going for.

The story behind why the 390 and 580 exist is relatively long, and includes some engine models that were never produced for various reasons.
 
Considering my IO-360 is coming up on overhaul, my thought was if there was an STC, i could spend a little extra for a little better climb performance. But like someone else said, it'd probably be better to step up to a bigger plane if i want more power. But it'll be a while before I do that, I really like the arrow actually, I just wish it had something like 260 horses to power it.
 
Undoubtedly there are some fleets that tend to have the types of owners that want their planes tricked out, while there are some fleets that do not feel that way at all. I don't know where the Arrow falls into the market there,

Are you saying my Arrow ownership says something about my attitude towards this avocation? Don't answer that, I'm being rhetorical...:D.

Considering my IO-360 is coming up on overhaul, my thought was if there was an STC, i could spend a little extra for a little better climb performance. But like someone else said, it'd probably be better to step up to a bigger plane if i want more power. But it'll be a while before I do that, I really like the arrow actually, I just wish it had something like 260 horses to power it.

LOL. Welcome to Arrows Anonymous; sounds like you've been to one of our meetings already. Just remember, we try not to blame Comanches for our lot in life, we just take it... one day at a time. :D

On a more serious note, part 23 killed my dream of engine retrofit.
 
Part of the goal with those STCs was also to go after particular markets that were heavily PMA'd from an engine perspective (i.e. using aftermarket cylinders, going to 3rd party overhaul shops, etc.) to try to bring money back into the company. So it's not just a raw number of aircraft that they were looking at, it's also what people are doing with those engines at overhaul time. The other consideration was how many of the owners were expected to go with the upgrade, which has to do with the demographics. Undoubtedly there are some fleets that tend to have the types of owners that want their planes tricked out, while there are some fleets that do not feel that way at all. I don't know where the Arrow falls into the market there, but it has angle valve cylinders for which Lycoming is the only source if you need new ones. Also going from 200 to 215 HP has less of a benefit than 180 to 215 HP, which was typically the jump they were going for.

The story behind why the 390 and 580 exist is relatively long, and includes some engine models that were never produced for various reasons.

I figured that was all factored into the decision. It still doesn't seem like either the Mooney or Cardinal group is a big enough segment to make it worth pursuing. On the other hand, it might have been a good decision to help offset the development costs of the engine if it was something that got developed and certified, then corporate realized that there was no market for an engine they just created. :)
 
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