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  #11  
Old 09-20-2013, 03:39 PM
David Paule David Paule is offline
 
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Quote:
Originally Posted by Grezdlitn View Post
Most of the Continentals I'm familiar with have keel mounts akin to the Beech Bonanza. To adapt a keel to Vans traditional firewall construction is probably too expensive and time consuming.
Shouldn't be. My Cessna 180 has a keel-mounted (more properly termed a bed-mount, I think) engine and a conventional engine mount connection to the firewall.

There's no requirement that it be made like a Bonanzas, unless it's for a Bonanza.

Dave
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  #12  
Old 09-20-2013, 03:42 PM
GhostRider32 GhostRider32 is offline
 
Join Date: Jun 2013
Location: Paris, Tx
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Well, most of these answers sound like decent reasons of why Continentals usually aren't seen on RV's, I'm just a believer that more choices are better than fewer choices, most of the time.

Maybe I'm using the wrong plane so let's compare a closer set of engines.

Vans says that the 9A flies very well on the 118hp Lycoming O-235 so other than the mount, it seems that a 125hp Continental O-240 would be a potentially decent choice given that the weights are similar.

What say ye........?
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  #13  
Old 09-20-2013, 03:45 PM
GhostRider32 GhostRider32 is offline
 
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Location: Paris, Tx
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Quote:
Originally Posted by Kaffer62 View Post
That is for the powerplant kit. Includes propeller and firewall forward necessities

Per Vans

Powerplant Kit:contains new Rotax 912ULS engine,engine installation kit and a Sensenichcomposite ground adjustable propeller
Fair enough, I was thinking it was just the engine.
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  #14  
Old 09-20-2013, 06:19 PM
rv7charlie rv7charlie is offline
 
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Location: Pocahontas MS
Posts: 3,884
Default Too heavy?

Continental IO-360:

General characteristics
Type: 6-cylinder, fuel injected, horizontally opposed, piston engine
Bore: 4.438 (112 mm)
Stroke: 3.875 (98 mm)
Displacement: 360 in? (5.90 L)
Dry weight: 294 lb (133 kg)

Performance
Power output: 195 hp (145 kW) at 2,800 rpm continuous, 210 hp (157 kW) at 2,800 rpm for take-off
Compression ratio: 8.5:1
Power-to-weight ratio: 0.71 hp/lb

Having 6 instead of 4 cylinders is no guarantee that the engine will be heavier. (It's actually likely that it will be lighter at the same performance level; ask a structural engineer or an F1 race car engine guy why.)

Bigger factors for most would likely be the ~50% higher overhaul cost for cylinders and the shorter TBO (~1500-1600 hrs for the Continental), and the monster: you can't plug & play with the Continental (no support from Van's).

Ask a few Globe/Temco Swift drivers which they prefer. (And remember, it was designed for an 85 HP engine).

I can tell you that I've co-owned a Lyc IO-360 powered swift, & flown a Cont IO-360 powered Swift, & the Continental was significantly more impressive on takeoff. And it was...smooooooothhhhh. And then there's that sound. One of my neighbors has a Cont. Swift with 6>1 exhaust, and it's hard to describe how good it sounds compared to a 4cyl Lyc. If I were using a conventional a/c engine on my -7, I would give the Cont. serious consideration. But I do have a neighbor who's both a structural engineer and an accomplished welder. :-)

If you get an honest answer from Van's it will almost certainly be that they don't like them because they aren't familiar with them & they don't want to fool with with supporting a 2nd (now 3rd) engine line. Ask yourself if the -12 would have a Rotax if there was a Lyc that could be forced into working. (I'm pretty sure I know the answer).

Charlie
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  #15  
Old 09-20-2013, 06:26 PM
Kyle Boatright Kyle Boatright is offline
 
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Location: Atlanta, GA
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Van's struck an OEM deal with Lycoming years ago. I'm sure they get great pricing on Lycomings, and would bet that the Lycoming deal wouldn't be as favorable if Van's went away from being an exclusive Lycoming "house".

Since Lycoming doesn't have a product that competes with the Rotax, that exception probably doesn't bother them.
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  #16  
Old 09-20-2013, 06:27 PM
lostpilot28's Avatar
lostpilot28 lostpilot28 is offline
 
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Quote:
Originally Posted by GhostRider32 View Post
Where do you see that? Vans own price list shows $27,885 for a 912 uls.
Lockwood aviation. They're in Florida, I think.
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  #17  
Old 09-20-2013, 06:32 PM
GhostRider32 GhostRider32 is offline
 
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Quote:
Originally Posted by rv7charlie View Post
Continental IO-360:

General characteristics
Type: 6-cylinder, fuel injected, horizontally opposed, piston engine
Bore: 4.438 (112 mm)
Stroke: 3.875 (98 mm)
Displacement: 360 in? (5.90 L)
Dry weight: 294 lb (133 kg)

Performance
Power output: 195 hp (145 kW) at 2,800 rpm continuous, 210 hp (157 kW) at 2,800 rpm for take-off
Compression ratio: 8.5:1
Power-to-weight ratio: 0.71 hp/lb

Having 6 instead of 4 cylinders is no guarantee that the engine will be heavier. (It's actually likely that it will be lighter at the same performance level; ask a structural engineer or an F1 race car engine guy why.)

Bigger factors for most would likely be the ~50% higher overhaul cost for cylinders and the shorter TBO (~1500-1600 hrs for the Continental), and the monster: you can't plug & play with the Continental (no support from Van's).

Ask a few Globe/Temco Swift drivers which they prefer. (And remember, it was designed for an 85 HP engine).

I can tell you that I've co-owned a Lyc IO-360 powered swift, & flown a Cont IO-360 powered Swift, & the Continental was significantly more impressive on takeoff. And it was...smooooooothhhhh. And then there's that sound. One of my neighbors has a Cont. Swift with 6>1 exhaust, and it's hard to describe how good it sounds compared to a 4cyl Lyc. If I were using a conventional a/c engine on my -7, I would give the Cont. serious consideration. But I do have a neighbor who's both a structural engineer and an accomplished welder. :-)

If you get an honest answer from Van's it will almost certainly be that they don't like them because they aren't familiar with them & they don't want to fool with with supporting a 2nd (now 3rd) engine line. Ask yourself if the -12 would have a Rotax if there was a Lyc that could be forced into working. (I'm pretty sure I know the answer).

Charlie
Some very good points. I didn't realize that the Cont. IO-360 had a TBO of 1600 hours.

There are definately some differences between the 2 manufacturers and there may not be a lot of interchangeability in some most models but it is interesting that the Cont. IO-240 and the Lycoming IO-235 "appear" to be nearly interchangable for the 9 or 9A.

I can see how Van's would want to keep it within one engine line as much as possible to keep it as simple as possible.

It would be cool to see someone put a IO-240 on a 9A and compare the performance to the IO-235.
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  #18  
Old 09-21-2013, 05:28 AM
rwhittier rwhittier is offline
 
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Location: Glendale, AZ
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Default Some are higher TBO

The IO-360-ES, for example, has a 2000 hour TBO.

Quote:
Originally Posted by GhostRider32 View Post
Some very good points. I didn't realize that the Cont. IO-360 had a TBO of 1600 hours.
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  #19  
Old 09-21-2013, 07:32 AM
rv7charlie rv7charlie is offline
 
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Location: Pocahontas MS
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Quote:
Originally Posted by rwhittier View Post
The IO-360-ES, for example, has a 2000 hour TBO.
I haven't paid much attention to the TBO numbers in a long time.

This is excellent news, & even more reason to consider a Cont., if someone is willing to do the extra work on the motor mount.

Charlie
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  #20  
Old 09-21-2013, 07:58 AM
BillL BillL is online now
 
Join Date: Sep 2007
Location: Central IL
Posts: 5,516
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Being a numbers game, the Conti probably fares well, but I suspect the choice was the effect of management - Conti management. They made some poor choices in management in the 90's. They were not inclined to sell to the experimental market when I was there, and suspect that could have been another factor for Vans selection. Vans has to rely on good support from vendors and steady support for issues.

Having said all that, a well designed/documented installation for an I-6 would be a very interesting comparison to the standard. W&B, performance, and fuel burn, etc comparisons would be very interesting.

Where are our Conti guys?
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