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Why no IO-360 in RV9A?

Looking at RV-9A or RV-14. Seems like the market is moving towards the 14?

While weighing this out RV9A or RV-14A, was wondering if anyone has installed an IO-360 in an RV-9A? Wondering why recommended engine is limited to a 160hp 320.

Thanks!
 
Why no IO-360

After flying my RV-9A for several years, the idea of building one with an O-360 makes little sense to me.

Obviously, the most important reason is that the designer of the aircraft thinks it's a bad idea. To me that's a full stop.

But also: I don't need more speed or climb. An O-320 gives superb performance, and you can easily get into the yellow arc (and beyond!). If I could have anything, it would be increased load and more gas on board. Installing an O-320 versus an O-360 basically gets you both - the O-320 is lighter and burns less gas.

If I was shopping for a used RV-9A and found a good one with an O-360, that wouldn't slow me down any. But all else being equal, it wouldn't be my first choice for a powerplant.
 
After flying my RV-9A for several years, the idea of building one with an O-360 makes little sense to me.

Obviously, the most important reason is that the designer of the aircraft thinks it's a bad idea. To me that's a full stop.

But also: I don't need more speed or climb. An O-320 gives superb performance, and you can easily get into the yellow arc (and beyond!). If I could have anything, it would be increased load and more gas on board. Installing an O-320 versus an O-360 basically gets you both - the O-320 is lighter and burns less gas.

If I was shopping for a used RV-9A and found a good one with an O-360, that wouldn't slow me down any. But all else being equal, it wouldn't be my first choice for a powerplant.

That's pretty much where I'm at. If I can climb at 2000 fps and cruise at 150+ knots at 7.5 GPH (potentially outflying my bladder) and not doing aerobatics....

If aerobatics had been important to me, I'd have opted for a -7A rather than the 9.
 
I'll take the extra 20 HP @ 5700 ft. elevation/density altitude.

That’s kind of where I was going when asking about a 360 over a 320. Comparing the 9A to the 7A seems like 20 kn of cruise difference at altitude.

Seems like most people I talk to who owned an RV 7A really don’t do any aerobatics with the aircraft. I’m wondering why the 9A doesn’t have as much popularity as the 7A? What jumped out at me comparing the specifications of the two aircraft was the 7A cruising at 55% power is same as 9A at about 75% power.

Really appreciate your guy’s help and knowledge.
 
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Taking off from Lake Tahoe in a summer afternoon I really appreciate my IO360 in the 9. It’s also nice to have a great climb rate beyond 10k feet. Ive never flown one with a 320 in it, but I don’t think you can go wrong with the 360 either. As far as gas goes. I usually flight plan for 10-12k 150 knots LOP at 6.5 GPH. So it still does pretty good on gas as well.
 
I love the IO360 with constant speed prop in my 9A - it's a pure travelling machine now.
 
Taking off from Lake Tahoe in a summer afternoon I really appreciate my IO360 in the 9. It’s also nice to have a great climb rate beyond 10k feet. Ive never flown one with a 320 in it, but I don’t think you can go wrong with the 360 either. As far as gas goes. I usually flight plan for 10-12k 150 knots LOP at 6.5 GPH. So it still does pretty good on gas as well.

Not that taking off from Lake Tahoe or Truckee on a summer afternoon is a recommended practice in any piston airplane...
 
Not that taking off from Lake Tahoe or Truckee on a summer afternoon is a recommended practice in any piston airplane...

Not a great practice. But I've done it in 80 degree temps and had a good climb rate. Even with my fixed pitch prop. As long as winds are not strong over the mountains its doable. Would not try it in a spam can though unless it had some good power. Thats the advantage to the 9's wing. It performs much better in those situations.
 
Nope.

The throttle is just one of the flight controls in the airplane that the pilot must manipulate as needed to keep the airplane within it's flight envelope.

Can I get close to Vne if I want to? Sure - but so can an unpowered sailplane. Pilot vigilance is all that is needed, not a power restriction. Be a pilot, not a passenger.
 
Not that taking off from Lake Tahoe or Truckee on a summer afternoon is a recommended practice in any piston airplane...

Not sure why you say this. I used to live in Reno and went in and out of Tahoe occasionally. Not really an issue unless there are bad winds.

I'm very happy with my IO360 in the 9, especially for high density altitude airports. 320 does fine, but nothing wrong (in my opinion) with the extra hp. Better to have it and not use it than need it and not have it. Weight penalty is almost nothing between the two engines similarly equpped. My cruise fuel burn is as good or better than most.

My two cents since the original poster asked.
 
What jumped out at me comparing the specifications of the two aircraft was the 7A cruising at 55% power is same as 9A at about 75% power.

This is comparing the 200 hp 7A to the 160 hp 9A. With the same 160 hp engine Vans figures shows about a 3 kt difference at 55% and less at 75%.

Fin 9A
 
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That’s kind of where I was going when asking about a 360 over a 320. Comparing the 9A to the 7A seems like 20 kn of cruise difference at altitude.

Seems like most people I talk to who owned an RV 7A really don’t do any aerobatics with the aircraft. I’m wondering why the 9A doesn’t have as much popularity as the 7A? What jumped out at me comparing the specifications of the two aircraft was the 7A cruising at 55% power is same as 9A at about 75% power.

Really appreciate your guy’s help and knowledge.
Ok, so I will chime in here. Mainly because it sounds like too many people seem to be unaware of any other options other than the 320 or 360 [and no, I am not talking about auto engines). Why don’t you take a look at the Titan IO/O-340? I won’t bother with listing the info here. Just go to this link and check them out:

http://www.continental.aero/titan/engines/x340.aspx


Oh by the way 700 hours now on my 180 hp IO-340 with forward facing cold air induction. I have 360 power with 320 weights.
 
You only need a 320

Looking at RV-9A or RV-14. Seems like the market is moving towards the 14?

While weighing this out RV9A or RV-14A, was wondering if anyone has installed an IO-360 in an RV-9A? Wondering why recommended engine is limited to a 160hp 320.

Thanks!

Well because you don’t need a io320, you will go too fast with a 360, and your hair will fall out. Now, if you want a climbing homesick angel, and you can properly control the throttle, then you may be a candidate for a higher hp -9.
Picture this..... thousand one, thousand two....liftoff....... pattern altitude halfway down runway, throttle back to ~4gal/hr and 120mph (Carlson number) and enjoy the fuel economy (~30mpg).
Yep, it’s the real deal.
 
This is comparing the 200 hp 7A to the 160 hp 9A. With the same 160 hp engine Vans figures shows about a 3 kt difference at 55% and less at 75%.

Fin 9A

According to Van’s website there is an 18 mph/15.5 kt difference between the 9A and 7A at 8000 msl both 75% and 55% power. That’s pretty significant. I imagine the extra power is helpful at high density alts too.
 
Well because you don’t need a io320, you will go too fast with a 360, and your hair will fall out. Now, if you want a climbing homesick angel, and you can properly control the throttle, then you may be a candidate for a higher hp -9.
Picture this..... thousand one, thousand two....liftoff....... pattern altitude halfway down runway, throttle back to ~4gal/hr and 120mph (Carlson number) and enjoy the fuel economy (~30mpg).
Yep, it’s the real deal.

I’d rather keep my hair, and still get good density altitude performance. I’m pretty spoiled coming off a turbo normalized set up.

15-20kts more up high when I fly over the big pointy peaks here out west would be helpful.
 
I’d rather keep my hair, and still get good density altitude performance. I’m pretty spoiled coming off a turbo normalized set up.

15-20kts more up high when I fly over the big pointy peaks here out west would be helpful.

It's not the extra speed that I value so highly when crossing the mountains - it's the ability to maintain good flying speed while battling the downdrafts that frequent those mountains. When those guys come to visit, there ain't no replacement for displacement.
 
It's not the extra speed that I value so highly when crossing the mountains - it's the ability to maintain good flying speed while battling the downdrafts that frequent those mountains. When those guys come to visit, there ain't no replacement for displacement.

Exactly. Up high & high density alt HP matters. I like the extra stability the 9A has to offer, but would appreciate more power then vans recommended power plants.
 
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Nope.

The throttle is just one of the flight controls in the airplane that the pilot must manipulate as needed to keep the airplane within it's flight envelope.

Can I get close to Vne if I want to? Sure - but so can an unpowered sailplane. Pilot vigilance is all that is needed, not a power restriction. Be a pilot, not a passenger.

Bingo! There's a lot of planes that can overspeed at high power. Certainty they are usually considered high performance. At work several years ago at work, they wanted me to do night currency training in the plane instead of the sim (not my money), we leveled off at climb power and were a bit slow to pull the power back. We hit 230kias (249 Vmo) in the downwind by accident. Point being, oopsies happen, but don't happen as easily when there isn't enough power available to do it.
 
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