SonexBuilders.net

G'day all again,

In an effort to try and dig myself out of struggle town at the moment I was hoping someone may have had some experiences with the different cams that have been used on the Aerovee over the years. I currently have my Aerovee 2.0 stripped completely down in regard to that cracked engine case I posted about yesterday. So whilst it was apart I noticed it had a somewhat very different camshaft as to what is going to go into my Aerovee 2.1, that I have yet to build for my current Sonex project.

-Camshaft in the Aerovee 2.0 appears to be a Scat C-45

-Camshaft in the Aerovee 2.1 appears to be a Eagle 34 (2234) or cwc 34 is stamped on it.

The reason I ask about this is that the current camshaft I pulled out seems to be, by looking at it, quite a high performance cam for use in the higher rev range bracket 3500-6500rpm whist the 2.1 camshaft has the general look of it of a standard cam. However I can't find much info on the net about it. Generally speaking, to obtain the power in those higher rev ranges, usually the bottom end suffers which may explain why I have always felt my engine has always been on the anaemic side. The 3 props I have had made and tested never got to the rpm range that the manufacturer said it should be pulling and my climb rate in my aircraft has never been better than 350+ fpm solo.

Any help would be much appreciated as I'm not sure which way to turn now. I am about one more problem away from throwing the motor in the bin and putting a second hand Rotax 912 in my Aeropup no matter what the cost.

Attached are the pics of the camshafts to highlight the large difference in cam profiles.

My best advice is to contact someone who knows all about this stuff. ;)

Brett, I have 27 hours on my 2.1 Aerovee. We set it up for 8.0 compression. On its first flight we turned 3240 RPM. The plane climbs solo at about 800'/minute. My engine is an older one, serial #0163. We are running the standard wood Sensenich prop. I must say I'm impressed with the Aerovee engine. If you are doing a rebuild, have you thought of adding the turbo? I like the idea of the low rebuild cost with the Aerovee compared to all other engines.
You may want to talk with Jeff Lange at the Waupaca, WI, airport. He has a 2.0 Aerovee engine in a Sonerai I and has set several records with that plane. He flys in a race from somewhere in ND to OSH almost every year. His last race he average 201 mph in that plane. This year he has added fuel injection and a turbo unit to this engine. It will be real interesting to see what happens now with performance.
I have to believe based on other guys I know with the 2.1 engine that are getting very good performance also that something is not right in your old engine. You might want to try to talk with Harvey Plummer in Fond du Lac or Jim Zuege in Manitowoc to name a few. They all have the Aerovee 2.1 and like it. Have you talked with Joe Norris at Sonex? He is great source of info.
Let me know what you do.

I would imagine these two cams give very similar performance. Engle and Scat generally have very similar grinds across the performance envelope and many can be interchanged almost as if they're the same part. I think the people in the VW community generally will lean towards the Engle cam as they have earned a pretty solid reputation. I, however, have had nothing but good luck with Scat (currently running a C25 in my bus).

One thing I've read about these high performance cams is you need enough carb to push them. I suspect, if you're not developing the power you need, you should go through your fuel system and see if it's delivering the fuel your engine needs to breath. It could be something as simple as a new jet/needle in the carb or a clogged fuel vent.

Are you sure it's stamped "Eagle" because it's probably "Engle"? That might be why you're having trouble finding information on it.