Will a 914 Fit in a Model III?

[predmond]

I just bought a Model III with the "bump" radial cowl. I would like to upgrade the 80 HP N.A. Rotax engine to the turbocharged 914, either by swapping engines or with an add on upgrade like BullyHawk.

Can anyone tell me if there is enough room in this engine compartment to fit the turbocharged engine? Any other issues or concerns I'm not thinking about?

predmond

[Monocock]

Forgive me for asking but is a 912s not enough power for a Mk 3?

[Av8r3400]

In Henderson Nevada he may have density altitude problems...

My IV engine mounts would not accept a 914 without heavy modifications.

[War Eagle]

I fly a S7 with the 914. The S7 has the motor mounts moved forward several inches compared to the earlier models like the S5 and S6. This allows for a change in the W&B but also allows room to install the Rotax engines that use the airbox. (ie, 912s, 914)

I believe you would have to do some major mod on your engine mounts to provide the room to add the 914 and then I think you will have W&B issues to contend with. The gross on that plane is much lower than on the newer series of Kitfox planes also.

Not sure it can be done.

[predmond]

Thanks to all for the helpful info.

Regarding why I need the turbo; it's on amphibs and I want to base it at my second home near Lake Tahoe. Most lakes in the area are at around 6,000' MSL, with DA's routinely over 8,000', so, according to the charts, it's only making around 60HP. Can't get off the water without cool weather and a stiff wind. I love the little plane and would rather upgrade it than swap planes if possible.

[Monocock]

At sea level that would be one hell of a machine!!!

[Av8r3400]

8k+ density altitude is pretty high for an amphib with only 80 hp.

With all of the hard piping needed on the 914, you would need to modify the location of the oil tank and several structural members of the engine mount. I don't think it would be impossible, but it would be very difficult. The fiberglass cowling would be the easy part to modify.

I wonder if the ULS (100 hp) would be sufficient if used with a super-efficient prop like an IVO with the electric adjustment? This would be a bolt in without any structural modification.

[predmond]

Yes it is very thin air for this aircraft. On the ferry flight to CA from WI, over the Continental Divide, I nursed it up to 11,000 MSL (DA was over 12) and landed at a DA of 9100. It is not very safe at those altitudes, operating at the margins of its capabilities.

Regarding the ULS, a hangar neighbor has a Rans S6ES amphib with the 100 HP and has the same problem. He's looking to upgrade to turbo as well. I'm talking with a local shop about the project, but given the challenges, I may just reposition this plane to my Henderson, NV hangar and enjoy flying it on the Colorado river and lakes Mead, Mohave, and Havasu.

[catz631]

Me too Monocock ! All we have here are swamps,humidity ,bugs,rednecks and crocagators ! I sure miss mountains !!!
Dick Maddux
Milton,Fl

[av8rps]

Thanks to all for the helpful info.

Regarding why I need the turbo; it's on amphibs and I want to base it at my second home near Lake Tahoe.

Before you go through a lot of expense and hassle changing out an engine in your kitfox, try putting a 72" 3 blade IVO in-flight adjustable prop on your Kitfox. I fly a Model IV-1200 on amphibs with a 80 hp 912ul, and because of that prop I never had to install the 100 hp 912 I bought for it. With the IFA IVO prop I can now get max rpm on my takeoff run, cutting my takeoff time in half. Maybe you'd see something similar in your situation?