Bob,
Yes, a few people have installed the O-235. There is a local -9A with the 108 HP version of this engine. This is the guy's 2nd RV and replaced a -6A. He likes the 108 HP -9A much better than his -6A which he gave to an uncle or some such.
Although I installed an O-290-D2 in my -9, a lot of the issues you are going to run into with the O-235 are the same. The install is detailed on the
engine page of my web site.
I bought the install kit for the O-320 and modified it. The exhaust stack gets cut down (narrowed), I had Van?s send me a throttle bracket w/o the carb holes pre-punched so I could drill them to match the small MA3 carb, the baffles (old style kit) wouldn?t work as the cylinder head bolt holes are in different locations, and more little fun details. I don?t know if the O-235 has this same issue or not. It wasn?t a big deal to modify the baffles to fit, just another thing to do before I could go flying.
You will also need a longer than standard engine mount and cowling. This is actually a good thing as you wind up with a full 12? (30.48 CM) between the firewall and the engine. The standard mount is 2? (5 CM) shorter. That winds up making it easier to work behind the engine.
One suggestion, put at least one electronic ignition on your engine. I have dual P-mags and that really added a lot of extra power. There is also an STC (not that we care) to put high compression pistons in the O-235 which will bump it up to 125 HP.
As for the prop, go with a Catto 68? dia by 64? pitch and you will be good to go. That?s what Catto sells to the RV-3 guys w/ O-235?s and what he sold me for my 135 HP O-290. I was able to over spin it like crazy, which made for a good climb prop with that larger engine. For the O-235 I suspect it will be just right.
Let me know if you have any questions.
