Sailor,

I had not seen the Diesel Giant trick, but I just reviewed the photos - holes that I have drilled in are far smaller - maybe 1/4-1/2 that size - his look awfully large ... I also just spread the holes at about 90 degree points.

While I can't prove it, I believe the extra flow of water as it heats up assists the heating effect on the tstat itself - perhaps ensure more positive opening?

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg