Panther Sport Aircraft Forums

Some FACTS from William W.
https://flycorvair.net/2013/12/23/dynam ... and-o-200/

Myron,

I have an O-235 L2C flying on my panther and absolutely love it. I bought a used core and rebuilt everything as a certified engine. I have lightweight starter and alternator and no problems whatsoever with weitght (I’m 205#). In addition I have one impulse mag and a surefly electronic ignition. I also went with the Ellison TBI. Couldn’t be happier.

If you find something at Air Salvage if Dallas, I’d be happy to put my eyes on it for you. I am about 15 away by air.

One suggestion......try to find one with conical mounts. Mine is dynafocal and it’s very cramped towards the firewall. If I could go back, I would have made an access panel on my firewall from inside the cockpit. Might be a good idea regardless. Let me know if you have any questions.

Cheers!
Sean

I bought an O-200 as you can modify it to obtain near 120 hp. Its been used as a racing platform for many years and proven to be a robust design. It is also lighter than an O-235. I plan to remove the mags and go with electronic ignition, use a lightweight gen, starter and removed the vacuum pump & gear, so I can get some more weight off. I also modified the oil pump to use the O-300 pump to increase and improve oil flow.

I bought this engine off Barnstormers and after teardown had to reject the crankshaft due to a cracked slinger ring. The hunt to find a reasonable priced crank took me quite a bit of time but was finally successful by combing Barnstormers daily until I found a reasonable target. (Note - good deals go quickly - watch daily and call immediately) New from any source is very expensive. Be very careful to whom you buy an engine from as there are plenty that want to take your money. The guy I bought my engine from was confident that the crank would pass, we were both surprised when it failed. He however stayed true to his word and refunded a portion back, which was greatly appreciated.

Weight will be an issue, unless you are a really small person so always be cognizant of that. The O-235 is a great engine and would have been my second choice. Had they had the Corvair "engine in a box" feature at the time I pulled the trigger for the 0-200 I probably would have gone with that. I would have bought the billet crank too. One of the great features is Dan has enabled the community to use the engine of their choice and even provided a reasonable option himself (Corvair).

After a conversation with Dan this weekend on engines. I was able to find a 0-235-c1 (117hp) on barnstormers with 700SMOH on it. I plan on doing a good inspection and slapping her in. Look at Barnstormers and Texas Ari Salvage. Depending on your price point there are a lot of good o-235's out there.

My current Champion 7ECA (1965 model) is powered by an O-200. I have the SkyTech push-button starter, that seems to work better than the old pull-start model. I bought this plane to get my tailwheel endorsement in, and to fly while I completed my current project, a Bearhawk Patrol. Someday I hope to build a Panther (or maybe a Cougar - we'll see).

The interesting thing is when comparing my airplane's performance to that of another 7ECA based at the same airport, but powered by a Lycoming O-235 (115 hp model). The performance of the O-235 powered airplane is much greater than my O-200's... It takes off shorter, climbs significantly faster, and cruises faster than mine, despite the fact that the O-235 model is always flown with a student and CFI on board, and mine is usually solo, with 1/2 fuel of less.

That got me curious, and I began researching... What I found was pretty interesting. One of the guys who is a recognized Continental engine rebuilder (specializing in the smaller engines) swears that the O-200 puts out only about 90 HP in stock configuration. He has dyno'ed O-200s against C-85 and C-95 engines, and the results place the O-200 right between the other two engines.

So using that "90 hp" assumption as my starting point, I began doing some performance calculations, extrapolating what the 7ECA O-235 manual performance tables might look like if the engine was a 90-hp engine instead. The short answer is that it pretty well mirrors how my plane performs today. So while that is not conclusive proof by any means (my prop is not exactly in perfect condition - but neither is the O-235-powered one's), it does lend a bit more credence to the "O-200 actually is a 90-hp engine" theory...

It is compelling to me that once Bellanca began offering the choice of O-200 or O-235 in their 7ECA (the year after mine), something like 90% of the planed went out the door with the O-235. The next year, Bellanca discontinued the O-200 offering.

Since both engines seem to sell for roughly the same price, I would opt for the O-235 over the O-200 every time. It may be a little heavier, but it definitely makes more than enough additional power to make up for that difference. And the O-235 has a higher TBO (2000 to 24000 hours – depending on specific model, versus 1800 hours for the O-200).

I love my 7ECA, and chose it specifically for the O-200 (because it maximizes useful load, and I needed to get my "super-sized" body plus a CFI in there, and still legally carry enough fuel for training). But I sure would like to have that extra power on those 105ºF summer days, when I'm looking at 200-250 fpm max climb rate!

Please let me know if you have any leads on either a usable or buildable 0235 or 0200. Also appreciate any pros and/or cons for these engine options. Sorry if this is a repeat. Tried posting earlier and it did not seem to go.

Myron Callaham
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