What is the “highest” HP someone has put into a Kitfox?

[jiott]

Jeff, I agree with all that you said; however I would like to point out that probably 95+% of us on this forum are not really the kind of "experimenter" that you are referring to. Most of us just want a well engineered, safe, good performing, efficient, reliable, easy to build airplane. We have found that in the mainly standard Kitfox, and it so happens that it is designated "experimental". We like that because it allows us to make more or less minor changes to personalize our aircraft. Because of this you must forgive our comments and advice that appears to you and a few others as stodgy and not very cutting edge. We are just speaking to the majority of folks who follow this forum. Don't get me wrong, I enjoy hearing from those who are truly pushing the limits and adding to the knowledge base for all of us.

[NinerBikes]

Vne is expressed in mph, not kts?

[NinerBikes]

If you want to be like everyone else then by all means stick a Rotax on the front and call it good. If you want to be different and/or have the skill to tackle a complex project then do something different!
Range is not a concern for 99% because our bladder or butt won’t sit that long.
Going faster is not the issue. Everyone knows what the airframe limitations are.
It’s all about performance.... Yes some of us want to hot rod our Kitfox!
Build it, document your performance and let the group know what you found. The purpose of experimental aviation is to learn something. Kinda hard to do if you repeat what everyone else does...

I would suggest, also, that Experimental is a way to keep your expenses down while being able to afford to fly... by doing your own maintenance, checks, 100 hours, annuals, whatever. Everyone's needs and missions are different. I'd be happy as a clam in a used SS5, 6 or 7 with trike landing gear. Who knows, maybe even in a Van's RV-12, too.

[brjohnso]

What are you trying to accomplish? Significant improvement in performance (beyond what others have already done) is probably going to require changing more than just the engine. Other components will probably have to be changed to take full advantage of that horsepower.

[Esser]

Yes, for some reason the experimental crowd loves mph instead of kts.

Fabric isn’t the limiting factor for the Vne. It’s flutter on a pretty flexible wing.

I don’t have much time on my plane but at 75% power I’m cruising at 128mph. 914 with fuel injection and CS prop.

[jiott]

Not having been a pilot previously, when I started flying my Kitfox with a Dynon Skyview panel I went back and forth with setting speeds and distances in knots or mph (the settings are easily changed). I finally chose the mph since that was what I was familiar with. I guess I'm not a "real" pilot, but at least I can relate to it.

[rv9ralph]

I have been associated with experimental aviation since the 90's. I have found that most that have tried engine conversions (those that have not been extensively engineered for aviation) spend most of their time working on engine issues and not flying.
The other thing...

Fabric isn’t the limiting factor for the Vne. It’s flutter on a pretty flexible wing.

Fabric was used on many aircraft of WWII. i.e control surfaces on F4U Corsairs capable of 400+ mph.

Ralph

[Slyfox]

kts is what ATC uses. My gps in each airplane is set up for KTS because of this. makes understanding tower and such easier. I use KTS for the rv on all accounts. the Kitfox on the instrumentation is mph. It actually makes sense. On final and up to landing with the rv in kts it backs off the reading in reality to the kitfox 15%. so going back and forth in aircraft I'm a little closer in my reading coming in to land. you may not understand, but it really does work. if I hit 70 in either airplane on final, I'm pretty close no matter which one I fly. over the numbers I want 62kts in the rv, 50mph in the kitfox. works for me. but the gps having Kts on both really works, that's what atc goes by. also, both aircraft has the steam gauges for airspeed. so, I just glance and see a pointer in the right area mainly. works for me. Oh I have the dynon d180 in the rv. I never use it to land. hate it. steam all the way.

[Av8r3400]

Vne is expressed in mph, not kts?

Yes. It's an airplane, not a boat.

[Rik]

I would suggest, also, that Experimental is a way to keep your expenses down while being able to afford to fly... by doing your own maintenance, checks, 100 hours, annuals, whatever. Everyone's needs and missions are different. I'd be happy as a clam in a used SS5, 6 or 7 with trike landing gear. Who knows, maybe even in a Van's RV-12, too.

You will like the RV12. I have about 60 hrs in one. Super easy to fly, super easy to land can handle a decent cross wind.