Engine for SS7

[Flienlow]

SO....when it comes to engines for the Kitfox it looks like you have a few choices:

1. Rotax 914 $30+K (115HP)
2. Lycoming 233,235 $25-30+K (115HP)
3. Rotex radial $25k (not in the scope of this debate) (110HP)
3. Rotax 912 $19k (100HP)
4. Viking $14k (110HP)
5. Corvair $6k (110HP)

There are a few others like Jabiru, but you get my point.

We all know the 912 is the gold standard and would be the easiest over all to install. And most important it is supported by the manufacturer. Logic would tell me that is route to take.

The problem I have is with #5 because cost definately is a factor. I have never built an airplane before and have no experience owning or maintaining one. I damn sure dont want to trip over a few dollars and fall from the sky in a torrent of hell fire because I was "cheap" either. However, from what I have been reading (and I can only go off the info that I have found so far) the Corvair engine can be made extremely reliable, and is a HIGHLY cost effective power plant.

The benefits to me are:
1.Cost- its affordable
2. I can source my own engine
4. parts availablity
5. this is something I can tinker with and build myself. (-After all this is why we are doing this correct?)

Cons:
1. difficulty installing, engine management, cowling,ect
2. Needs carb heat to prevent icing.
3. not supported by manufacturer.
4. Engine is older than me.
5. What I dont know may kill me...

I know of one Corvair proponent on this site (and thank you John) but before I start throwing money around (even if its only a $100 for a Core, or $50 for a book) I would to hear the thoughts of others and glean as much information as possible.

Thank you in advance.

[Monocock]

I can't help feel that what you might save in initial purchase cost with #5, you'll soon be spending on the additional installation issues, delays and frustrations.

Yes, the 912S might be $19k, but it's an engine that will easily bolt in, and then run for hundreds and hundreds of hassle free hours.

What about buying a <500 hour 912S for $10k??

[DanB]

SO....

1. difficulty installing, engine management, cowling,ect
2. Needs carb heat to prevent icing.
3. not supported by manufacturer.
4. Engine is older than me.
5. What I dont know may kill me...

I know of one Corvair proponent on this site (and thank you John) but before I start throwing money around (even if its only a $100 for a Core, or $50 for a book) I would to hear the thoughts of others and glean as much information as possible.

Thank you in advance.

Fleinlow,
I believe it might boil down to how much of an engineer / tinkerer you are. With the #5 (What I don't know may kill me) statement, are you willing to bet your life on understanding this application?
That being said, there are several Corvair engines pulling planes behind them. I know a guy in my EAA chapter that did a great job installing one in a Zenith Zodiac 650, however, he IS an engineer that was confident in his understanding of the build. FWIW

[Av8r3400]

This topic has been beaten around for years. It has been stated here before; these are “experimental” aircraft. If you want to be an experimenter, more power to you. Have fun. You’re starting with a great airframe design and concept.

Keep in mind that experimentation is all about failures. Sure the motor (VW or Corvair) will be less money than the known quantities (mainly Rotax), but there are a multitude of other costs. You will have motor mounts, cowlings, propellers, fuel systems, cooling systems, weight and balance, on and on and on, to contend with. As an experimenter you will be designing and manufacturing several of each of these. The first designs will almost surely need to be reworked, maybe several times. Some of these items may be available pre-made, some may not. You will be dealing with it all.

The Avid/Kitfox design has been around for nearly 30 years. The aircraft conversions of the VW and Corvair motors have been around far longer. If these motors worked in these planes there would be many of them flying. In truth, there are very few. This alone speaks volumes (to me at least).

If you want an aircraft that will be a known performer, in the way the airframe was designed, the Rotax 912 series of motors is worth the money and will be far less costly in the end; both in a time and money sense.

[Flienlow]

Ya know....I am starting to see a pattern here. Point taken gents.

Thank you.

[DesertFox4]

This topic has been beaten around for years. It has been stated here before

This is so true. Our forum is still attracting new folks all the time and even though we get some of the same questions raised every so often it's really gratifying to see our members take time to respond with experience and opinion to assist a new member. Thanks to all that roll out the red carpet for our new members on this post and future posts.

P.S. Fleinlow- I concur with the previous responses to your question however, if you don't have a Kitfox airframe to mount an engine to then you don't have an engine decision problem yet. Order the kit, start building and you will still have 1 year, if you're a fast builder, or more to make the final engine decision. You'll be that much further ahead of all the prospects still mulling over engine choices.