Earlier, Sport Pilot wrote:

My bad, the VW is a boxer, not sure about the Corvair.

Here's a picture of the Corvair crankshaft from William Wynne's Fly
Corvair site:

http://www.flycorvair.com/crank.jpg

I count ten journals on that crank (not counting the stuff forward of
the cam drive gear or aft of the distrubutor drive gear). Since it's a
six cylinder car, I have to assume that four of those (the first,
fourth, seventh, and tenth) are mains that ride in bearing shells in
the crankshaft. That leaves six journals for the connecting rods; to my
way of thinking that means that the con rods are not sharing journals.

As to whether it's a true "boxer," it looks to me like it is. I think
that the photo shows that the rod journals in each opposing cylinder
pair are separated by 180 degrees. That shows most clearly in the rod
journal pair near the bottom of the photo. Since its a 6-cylinder
engine the different pairs are separated from each other by 120
degrees, so the other pairs are at odd angles to the photo perspective.

As for the Lycoming, this drawing from the Sacramento Sky Ranch
(thanks, Mr. Schwaner!) shows seven journals, of which three (including
the long one behind the prop flange) are mains and four are rod
journals:

http://www.sacskyranch.com/lyc_crank_gear.jpg

And again, the rod journals of each opposing cylinder pair are
separated by 180 degrees.

Thanks, and best regards to all

Bob K.
http://www.hpaircraft.com/hp-24