Engine upgrade

[924549]

I am looking at changing out my 582 grey head for a 80hp 912 this winter. Does anyone have experience or help full information that I could use. I am not sure about things like using my old cowling, weight and balance and increased gross weight.
Any info to get me started on the right track would be appreciated.

Pieter

[HighWing]

Pieter,
I once helped a friend finish the engine swap. Another guy did the actual engine swap and I modified the cowl. It amounted to adding a longer lip on the aft edges of the bump cowls. I don't recall how much I added - probably between an inch or two, but it is definitely doable.

Another thought on the swap. The owner of the Model IV recently did the Zipper cylinder conversion and it was suggested that he use the new split throttle cable available from Kitfox. What was originally done was to just put in longer cables from the splitter that came with the original 582 set-up. My friend decided to go with what he had because the new throttle didn't have the vernier knob and using it had become part of his flying routine.

[egp8111]

Pieter
I swapped out a 582 for a 912 in my KF III. It makes a nice winter project. I was able to scrounge up all the major parts used (motor mount, exhaust and muffler) and saved a lot of $. You can use the same cowl but you have to add about two or three inches of glass back on the rear edge to make it fit. no big deal. Same radiator as the 582. Just follow the manual and dont try to reinvent the wheel and it wont be too bad a job. Highwing is right, go with a dual cable throttle set up, much simpler.
It made the KF III a real little hot rod. It would be off the ground before I ever got the throttle all the way in and the 912 will easily drag it past redline. It did require a few pounds of lead to the tail for CG.

EG

[rdooley79]

You might consider the Rotax 670. It makes a lot of power and is an easier swap. I can say that it makes a lot more power than the 582 that was in the bird earlier. Call Rotax Rick and he can answer all your questions. Search Barnstormers for rotax 670 and you'll find him.


http://www.teamkitfox.com/Forums/showthread.php?t=5500