Fellow air-cooled heads:

Another gem from the archives of the VW Autoist, September,
1967 for those out there who may be *very* picky about their
timing.  Under the heading *Bug Dust* by Hank Weisner is the
following:

<quote>For those of you who can't keep your cotton pickin
hands out of the engine room, we would like to remind you
that when timing a 1965 or later Bug, you will find that #3
cylinder is late firing while the other three seem to check
out.  Don't worry--it is supposed to be that way.  The
reason #3 cylinder is late firing as compared to the others
is that in 1965 Volkswagen gave a special grind to the cam
in the distributor to cause #3 to fire 2-1/2 degrees late.
This was done to aid cooling of #3 cylinder which is
farthest away from the fan.<unquote>

It does *not*, however, say whether this is true of bus
engines as well.  Frankly, I never considered timing
anything more than cylinder #1, letting the rest just follow
along.  I *do* have to wonder why it took so long for VW to
incorporate this idea in their engines.

Also, (though it says nothing about the involvement of the
oil cooler in this problem) what is the impact of external
oil cooler systems on this?  IMHO, it is good reason not to
install external oil coolers (unless you also change the cam
to re-time cylinder #3 or you have a pre-65 engine).

Is there a moral here?

-Jim Bryant