IOW, concentrating on improving the airflow may be more
helpful than improving the fins.
---------------------------------------------------------------------------------------

Roger that. In spades. Most homebuilt cooling systems aren't. Go
over to AirVW and give a gander at what one of the Monnett's had to
say about VW heads.... and later what he had to say about VW cooling
systems.

x-number of inches of water-pressure differential between the inlet
plenum and the outlet plenum... takes something on the order of 90mph
to get that amount of pressure from ram air alone. And you're driving
a plane that cruises @ 75mph

So now you REALLY get to see the Wizards at work... guys like John
Thrope, with his equations for the inlet AREA of the plenum vs the
outlet area, with pieces of duck tape here & there and flat THROWING
the stock oil cooler across the hangar because it's making such a huge
HOLE in the back wall of his inlet plenum that there ain't no way to
get the required about of pressure... and the Great Designer insisting
he's NEVER had any 'trouble'... and it reminds you of the guy in
Oregon with his three engines but never any trouble, or the guy in
Canada with 1300 hrs on the SAME engine over a 20 year period and
NEVER ANY TROUBLE... but forgetting to mention the ANNUAL 'freshening
of the valves' and the occasional replacing of the bearings because
THOSE THINGS DON'T COUNT as 'troublle' since he's never had any in all
those long, long twenty whole YEARS of flying.... which worked out to
something like 65 HOURS OF FLYING PER YEAR, between June and
September, because that is the flying "..season..." according to this
particular expert with his high-time VP1 now a'dangling in some
museum.

The only thing more lovable than a VW-powered air plane is the folks
that owns them.

-R.S.Hoover