A couple folks wrote to ask for details about the oil cooler install. Sorry
to take so long, but it has shaped up to be a busy week.

System capacity increase: the system capacity will increase by 3.4 quarts.
The 45 feet of oil line will carry approximately 2.1 quarts, the larger oil
filter will add approximately .65 quarts, and the cooler carries about a
little more than half a quart. This roughly doubles the capacity of the
engine's oil circuit, lowering the workload on each little molecule of oil.
This is one of many factors that makes a Porsche 2.0-2.7 liter 911 motor so
durable, it is a small engine, with a LOT of oil. I think VW skimped on the
oil capacity for the type 4.

As far as concerns about the overall length of the oil circuit, I don't
have any. This is basically the same design as Porsche used on a number of
their production cars, with the oil cooler residing in the left front wheel
well (911, 930), or centralized up front in a cowling (917, 916). Further
many Baja, autocross, and IMSA racers use a similar overall design. As long
as the walls of the oil lines cannot expand, you have a decent hydraulic
circuit with no pressure loss, and minimal increase in load on the motor
due to the friction of pushing the oil through the lines.

As for "draining all the oil during oil changes", I don't plan to. In the
same way that you only change *most* of the transmission fluid during an
automatic transmission service, that is precisely how my oil changes will
work. Of the 7.1 quarts of oil in my system, I will change out
approximately 4.4 quarts with a filter change, leaving about 2.7 quarts
unchanged. No big deal. I get mostly new oil. I still see this as far
better than the overworked, overheated 3.7 quarts VW put in the design.

Finally, "drainback" shouldn't be a problem. The thermostat operates as a
check valve, as does a quality oil filter. Once the system is filled
(during install) it shouldn't ever need to be drained again. I may break
 the seal to install a second cooler if this one doesn't cut the mustard. I
may need to replace the rubber/braided hoses at some point, but probably
not any time soon. Other than those situations, it is a closed circuit, and
won't drain back into the crankcase.

I had a similar set up on my first 1976, and it worked great. That motor
lasted more miles than I can count, (cuz the odometer broke). It was one of
those "Quick-cool" 8-pass jeebers. Not the best cooler, but it helped.

Hope this helps.

G. Matthew Bulley
Bulley-Hewlett & Associates
www.bulley-hewlett.com
Cary, NC USA
888.468.4880 tollfree