The second 544 I had developed a crack just in front of the rear main
bearing. It may have been abused but I have never seen a B18 or
a B20 (or a B30, for that matter) with a cracked crank.
The B18 was a tremendous step forward in durability because of having
5 main bearings rather than 3, among other things. The B18 544 will easily
take a B20 engine, in fact it bolts right in. The B16 and earlier 544s/444s
are not so easy to change. Parts availability is somewhat of a problem
but to me the big issue is not the inferiority of the B16 - it was a good
engine. It is the superiority of the B18 and even greater superiority of
the B20. Like the guy on the commercial used to say about Dunlop tires,
"They wear like arn!!"
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma