Continental O-170-3 flat-4 engine, Wings Over The Rockies, Denver, Colorado
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/37467370@N08/">Greg Goebel</a>
<a rel="nofollow" class="external free" href="https://www.flickr.com/photos/37467370@N08/7451220094">https://www.flickr.com/photos/37467370@N08/7451220094</a>