Cessna 120-140 Association

I have a '48 140 with a C90 and a 7150 prop, VG's, metalized wings, 8.50 Dessers on clevelands and a scott 3200 tailwheel. Straight skis and trickair penetration skis. Empty weight is 956 on wheels. The idea of installing an O290 sounds great for all that horsepower, but the weight increase and cost really pushes the limits of reason. But, I might have access to a Lycoming O235-L2C from a friends plane. I see articles written on the subject, but no details. The only thing I have found is a McKenzie STC using a O235-C1 and its even in the TCDS, from 1955. But I can't find any more info on the subject. The biggest questions that come to mind are engine mount and propellor options. But I'm hoping someone can chime in and educate me on the subject. And since people put O320's in 150's, why can't that be done in a 140? Any one done it? why and why not.

I'm not aware of anyone installing an 0-320 in a 120/140. I'm sure it can be done, anything can. I've flown a Texas Taildragger with an 0-360, now "THERE" is an airplane. They use it to pull gliders...........and does it ever. (well..........not as good as a Piper Pawnee...........)
I think it would be overkill in a 120/140, but then..................depending on who you are........"there's no replacement for displacement!"

One of our members owns the McKenzie STC for the lycoming installs. Gus Warren, I can put you in touch with him if you would like.

I fly with an 0-200. that extra 15hp makes all the difference, (unless you're in the mountains or high elevations) It's still a 2 person airplane, with minimal weight penalty.

I have the 0235 Mckenzie stc on my 140 it has great power but the down side being the very tight fit. the cowling barely fits and I have to remove the prop and cowling to even do a oil change.

I am looking for someone who has the McKenzie stc for the o235 installation into a c120. I understand the owner of the stc May no longer be in business