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Honda 3.5 L, V6,*245 HP

It's at least 100 lbs heavier which could be a CG pain. I would probably put it in a non-aerobatic plane but not a 7 or 8. I also would have no problem flying behind it.
 
NDrv8r said:
wow, just the conversion kit is 16k. I paid 8600 for my IO-360.
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Add to that the additional cost of a custom engine mount, radiator, etc. Not to mention the time it would take to modify the cowling and other systems.

What I didn't see was any reference to a redundant ECU or other parts. (What do the other auto conversions run?)

It also looks like you need the auto style hi pressure fuel system. Is that necessarily a bad thing?
 
HP and weight overkill for 2 place RVs. Might be ok in an RV10.

Titan has been flight testing these for a couple years now and they work very well. The gearbox comes from Autoflight in NZ and is also well proven and respected. We supply the EMSs for all their Suzuki and Honda conversions as well as a new Turbo 912 under development.
 
Fly half way across Lake Michigan, just past the point of no return, then ask yourself, "do I want to do an auto-conversion"!
 
My friend lost his engine on his C182 halfway between Catalina Island and Long Beach. About 25 hours on a new engine when it went quiet.
Also I lost an engine on a TriPacer 20 hours after a new rebuild.
Sooooo, just because it's certified it doesn't mean it's going to NOT go out on you at the MOST inconvenient time.
 
JDanno said:
My friend lost his engine on his C182 halfway between Catalina Island and Long Beach. About 25 hours on a new engine when it went quiet.
Also I lost an engine on a TriPacer 20 hours after a new rebuild.
Sooooo, just because it's certified it doesn't mean it's going to NOT go out on you at the MOST inconvenient time.
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So true. I'm amazed that so many cert powered guys take such big risks flying single engine over terrain that is certain death if the engine stops. Two fatal accidents out here not that long ago when jugs separated over the Rockies.

Any engine can fail. If you've put yourself in bad place with no options thinking it can't happen to you, you may be in for a very bad day.
 
rv6ejguy said:
So true. I'm amazed that so many cert powered guys take such big risks flying single engine over terrain that is certain death if the engine stops. Two fatal accidents out here not that long ago when jugs separated over the Rockies.

Any engine can fail. If you've put yourself in bad place with no options thinking it can't happen to you, you may be in for a very bad day.
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I plan all of my trips along or near to highways. If that engine goes goodby, you can land on or near a road so that help can get to you right away. There are plenty of major E-W highways over the Rockies that can be followed without too many extra miles. To Carson City I follow 50; to Reno, 80; to Casper its 15, then follow 180&40 past Heber City to pick up 80. 'Lots of towns and airports along the highways.
 
elippse said:
I plan all of my trips along or near to highways. If that engine goes goodby, you can land on or near a road so that help can get to you right away. There are plenty of major E-W highways over the Rockies that can be followed without too many extra miles. To Carson City I follow 50; to Reno, 80; to Casper its 15, then follow 180&40 past Heber City to pick up 80. 'Lots of towns and airports along the highways.
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Me too, no rocks or forests or big lakes on my flight path either and no night flying too I might add. Like you say, does not usually add a lot of miles to the trip but lots of peace of mind. I use the same criteria whether I'm flying behind a Lyco, Conti, Rotax or Subaru because there is only one up front. It is a moot point what is stamped on the valve covers if it stops running.

The core 3.5 Hondas have been very reliable to date and the Autoflight gearboxes as well as long as proper prop MOIs are adhered to.
 
Honda

Hi guys,

FWIW, a friend of mine put a V6 Honda and belt redrive into his RV6. Looked great on paper, although heavy. He flew it for a while and despite tweaking exhaust and cams, had to resort to a supercharger to get it to perform. Shortly after a supercharger bearing seized and he damaged the aircraft in an off-field landing. He subsequently rebuilt the aircraft with an O-360

Martin
 
TSwezey said:
Has your minivan engine died on you?
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No, but then again it is not hooked up to a propeller pulling an airplane through the air. It's hooked up to a transaxle pulling a minivan around town which is what it was designed to do.
 
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Harvey said:
Hi guys,

FWIW, a friend of mine put a V6 Honda and belt redrive into his RV6. Looked great on paper, although heavy. He flew it for a while and despite tweaking exhaust and cams, had to resort to a supercharger to get it to perform. Shortly after a supercharger bearing seized and he damaged the aircraft in an off-field landing. He subsequently rebuilt the aircraft with an O-360

Martin
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Never been much of a fan of superchargers on aircraft engines or automotive ones. I don't see any need to used forced induction on a 200+hp engine going in a -6. Something was far from right if it didn't perform well. There is no need to be changing cams and this is usually just a bad idea IMO. Leave the factory engineering intact and you should have factory reliability and hp intact in most cases. I've seen too many supercharger and valve train problems on aircraft conversions over the years when people mess with this stuff.

The Honda will be heavy for sure in -6 as previously mentioned.
 
rv6ejguy said:
.... Leave the factory engineering intact and you should have factory reliability and hp intact in most cases...
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Except that .... when they designed the engine, they didn't design it to run continuous in excess of 5000 rpm required the get the hp out of it:eek:
 
MauiLvrs said:
Except that .... when they designed the engine, they didn't design it to run continuous in excess of 5000 rpm required the get the hp out of it:eek:
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Actually they did. All modern designs are validated by running between 200 and 400 hours at power peak these days. Multiple examples, not just one. With transmission testing and cold/hot weather testing, some examples are seeing 1200-1600 hours being flogged WOT at 4000-6500 rpm. Automotive engine testing today FAR exceeds what Lycoming and Continental do or are required to do in order to gain certification. I have described some of the tests in previous discussions in the Alternative Engines Sections.

Cruising at 4000-5000 rpm is pretty routine on the Autobahn and you don't see cars grenading their engines doing this.
 
Outside of being somewhat heavier than an air-cooled installation, I think most automotive engines are pretty much bullet-proof. Unfortunately, it is other things that go with installing these engines that is where they can go wrong. A well-engineered installation should be every bit as reliable in a plane as in a car.
One of the things that most people don't look at is the horsepower curve, which shows that the engine at lower rpm actually developes more WOT power than would be obtained from a linear projection. That's because at the high rpm where the engine is rated, the power curve has begun to fall off and have a lower slope. This means that as you back off the throttle to a lower engine, you will have a power reserve. So if it's rated at 200 hp at 6000 rpm, it can develope more than 150 hp at 4500 rpm at WOT. This can make a noticeable increase in rate-of-climb.
 
rv6ejguy said:
Actually they did. All modern designs are validated by running between 200 and 400 hours at power peak these days. Multiple examples, not just one. With transmission testing and cold/hot weather testing, some examples are seeing 1200-1600 hours being flogged WOT at 4000-6500 rpm. Automotive engine testing today FAR exceeds what Lycoming and Continental do or are required to do in order to gain certification. I have described some of the tests in previous discussions in the Alternative Engines Sections.

Cruising at 4000-5000 rpm is pretty routine on the Autobahn and you don't see cars grenading their engines doing this.
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The Honda V6, while it redlines at 6000-6500 (I'm too lazy to go to my garage and check) may have been tested to run at 5000 rpm for several hundred hours was not DESIGNED to operate at that level. It was designed to run between 800-4000 rpm on a regular basis. That testing is designed to determine a break point in the engine...remember that. So what you are saying is that you are comfortable running an engine on a regular basis at an RPM the manufacturer utilized to test for failure points. If you insist on running the engine at its limit your margin for failure has just gotten a lot smaller in my opinion. Having said that, I do agree that most auto conversions fail between the engine and the prop, not necessarily in the engine itself. So what is the answer...I don't know:D
 
aarvig said:
The Honda V6, while it redlines at 6000-6500 (I'm too lazy to go to my garage and check) may have been tested to run at 5000 rpm for several hundred hours was not DESIGNED to operate at that level. It was designed to run between 800-4000 rpm on a regular basis. That testing is designed to determine a break point in the engine...remember that. So what you are saying is that you are comfortable running an engine on a regular basis at an RPM the manufacturer utilized to test for failure points. If you insist on running the engine at its limit your margin for failure has just gotten a lot smaller in my opinion. Having said that, I do agree that most auto conversions fail between the engine and the prop, not necessarily in the engine itself. So what is the answer...I don't know:D
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Yup, they are designed to operate at at full power/ full rpm without failure and tested as such for hundreds of hours. I think I already said that.

They are OPTIMIZED to run at 800-4500 rpm. Engine redlines are set to meet performance standards and by careful engineering studies into the stresses and strength margins of all the parts. Engines are rarely tested to destruction on a widespread basis.

Yes, I'm comfortable operating auto engines at or near power peak rpm for takeoff because for over 25 years, I built street, performance and road racing engines for a living and understand the testing that goes into these designs and the stresses involved. Most Japanese designs have considerable margin and I've related some stories of Showroom Stock engines going hundreds of hours between overhauls on these pages previously while being flogged past redline on every shift, specifically Toyota 4AGE engines.

In any case, we generally do not operate aircraft engines at full rated power for very long either since aircraft don't spend much time at sea level or max rpm. It is no different with auto engines in aircraft. We might use 5000-5500 rpm for takeoff and between 4000 and 4800 for cruise typically. (I cruise at 4600 rpm usually).

The Honda J35 series will produce 180hp at only 4200-4800 rpm depending on version so in an RV6-8, you would not be stressing the engine at all. It's unlikely you'd be cruising at over 4000 rpm. Piston speeds are well within acceptable ranges at these rpms for good longevity.

The fact that many designs can run 10-20% over redline and be turbocharged to produce double or triple the factory hp output with no or minimal internal changes is testament to the very large strength/ design margins in these designs. Operating continuously at 55% of rated power in this case to match O-360 cruise hp is really nothing and routinely done on the marine versions of these engines and cruising on the Autobahn in Germany.

As Paul stated, the automotive core engine reliability is rarely a problem (assuming lay people don't mess with factory engineering), the problems relating to power loss are usually attributed to fuel, spark, cooling or gearbox issues. These need to be addressed with proper design and testing.
 
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It seems that if continuous load design is a significant concern that maybe marine engines would be a better source for an alternative power plant. Boats tend to be run at constant, high power settings much like a plane. I suspect many would be too heavy and others not intended for long tbos or exceptional fuel efficiency, but some might prove pretty interesting. Heck even PWC's are getting near 300hp now from engines that are probably not too heavy (though nor terribly efficient). Probably not ideal for an aircraft, but the motor in this thing is pretty impressive: http://www.kawasaki.com/Products/product-specifications.aspx?scid=23&id=484

Or if you want a v6, I'd think this would be a better starting point than the honda car engine
http://www.yamaha-motor.com/outboard/products/subcatspecs/103/specs.aspx

Or maybe even this if you like two strokes
http://www.mercurymarine.com/engines/outboards/optimax/proxs/?model=6
 
car motors

Been said over and over--freedom of choice for engines IS experimental. I choose not to install an engine NOT designed for aviation. Why? Too lazy and not qualified to engineer the additional support systems making a ground power supply aviation friendly. Having said that ,if someone would do the work for me and it was a proven system at a cheaper price than a LYC, I'd stand in line to buy it. $15,000 to $25,000 is too much for poor 'ol me to risk on something without a proven history. Good luck-- Somebody.!
 
BikePilot said:
It seems that if continuous load design is a significant concern that maybe marine engines would be a better source for an alternative power plant. Boats tend to be run at constant, high power settings much like a plane. I suspect many would be too heavy and others not intended for long tbos or exceptional fuel efficiency, but some might prove pretty interesting.
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theoretically it sounds good, but you have to remember they have an endless supply of water to cool them. Since many auto conversions have cooling problems when not set up correctly i would think this would be an even bigger stumbling block to converting to run with air cooling/ watercooling where you have such a limited amount of water to carry in the plane.
 
There are several guys running marine engines in air boats with good success.

Really, we keep coming back to this old mythconception about auto engine duty cycle. ALL the OEMs today run their new engines much longer and harder at higher power settings than is required for certified aircraft engines. They must past the tests or they simply don't make it into production. I've invited people on forums for years now to show me some evidence that auto engines are regularly blowing up in aircraft due to the sustained high power. Nobody has ever come up with anything to support this "gut feeling" they have. The invitation is still out there...

I've asked people to read some SAE papers detailing modern engine development and testing but I doubt if anyone ever has, they prefer to go with their feelings rather than facts it seems.

It is simply tiresome to keep reading unqualified nonsense like this. Just a snippet from Chrysler V10 validation testing I read recently- 500 hours WOT between torque peak and power peak rpms, three 500 hour durability tests, a general 500 hour test, an emissions certification test and 100 hours at max power to prove exhaust manifold durability. Truck engine validation was typically 800 hours of idle, light load and WOT TP to PP.

As far as cooling goes, we understand how to do that properly these days. Too many people look at the failure of poorly designed cooling setups from years ago and keep thinking all liquid cooled installations are like this...

While all this discussion is going on, many Subaru, Suzuki and Honda engines are flying successfully all over the world- kinda like the Bumble Bee that does not know it shouldn't be able to fly...
 
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For those who like to experiment with auto conversions there are some other American made engines that may offer development potential.

Such as the GM 3.0 L V-6 @ 264hp, Ford has a new V-6 producing 315hp not sure of the displacement.

There is a lot of potential for those so inclined.

Glenn Wilkinson
 
glenn654 said:
For those who like to experiment with auto conversions there are some other American made engines that may offer development potential.

Such as the GM 3.0 L V-6 @ 264hp, Ford has a new V-6 producing 315hp not sure of the displacement.

There is a lot of potential for those so inclined.

Glenn Wilkinson
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Yes, lots of great aluminum V6s a being built these days. Would be too heavy for 6,7 or 8s but maybe a good fit for a 10. Most of the 3.7 and 3.8 engines are over 300hp these days at around 6000 rpm.
 
Cooling was not an issue at all in my plane. If anything I had too much cooling. If I had I choice I would have flown behind my LS2 across the ocean versus a Lyco.
 
glenn654 said:
For those who like to experiment with auto conversions there are some other American made engines that may offer development potential.

Such as the GM 3.0 L V-6 @ 264hp, Ford has a new V-6 producing 315hp not sure of the displacement.

There is a lot of potential for those so inclined.

Glenn Wilkinson
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Being a Mustang guy I can help out with a tidbit of info here. The new Ford 3.7L V6 makes 305 HP.

On a side note, as a mostly non-participant in this forum I really like to read these threads about alternative engines.
 
rv6ej, I'm not so bothered by duty cycle, but where I think the marine engines may have an advantage is from an efficiency and performance perspective. A lot of effort goes into making car engines run and pull well across a really broad range of rpms and be very efficient at very low power settings. An engine tuned to be most efficient at higher power settings would, I think, be an improvement all else equal.

As far as ford v6s go, the 3.5L ecoboost fitted with a large, single turbo would probably be quite good as far as conversion engines go I'd think (the stock turbos are much to small to be efficient at high power settings I think). It makes around 360hp in stock configuration IIRC.
 
BikePilot said:
rv6ej, I'm not so bothered by duty cycle, but where I think the marine engines may have an advantage is from an efficiency and performance perspective. A lot of effort goes into making car engines run and pull well across a really broad range of rpms and be very efficient at very low power settings. An engine tuned to be most efficient at higher power settings would, I think, be an improvement all else equal.

As far as ford v6s go, the 3.5L ecoboost fitted with a large, single turbo would probably be quite good as far as conversion engines go I'd think (the stock turbos are much to small to be efficient at high power settings I think). It makes around 360hp in stock configuration IIRC.
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Most auto engines have best BSFC about 1000 rpm below torque peak rpm. This is the point where VE is still high and frictional losses low but the BSFC does not change a whole lot 500 rpm lower or higher than this figure on most engines. Overall, auto engines are generally more developed than marine engines with regards to fuel economy because mpg is such a numbers game and the competition is far more intense. There are some very cool marine designs out there now too for sure as many companies have applied the best auto derived technology to their marine designs.

I agree that the best route for many auto conversions is light turbocharging, for only a slight weight penalty, power is improved substantially, especially at lower rpms and you maintain power at altitude. This is especially true on smaller displacement engines which would otherwise have to be flogged at much higher rpms to develop reasonable power in cruise. For some of the modern, large V6s however, I'm not sure I'd go to the trouble of turbocharging as they make pretty decent power at relatively low rpms.

For sure, most terrestrial turbos are not well suited to aviation use but this is easily remedied with a proper turbo.
 
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