Aloha I'm beginning to restore my 1931 402 with an engine untouched since before 1954. When I pulled the drain plug and felt around, chunks of nasties was all I could find. The motor idled fine.
I have heard of either rebabbiting or conversion to shell bearings, cross drilling the crank for improved flow. I'm seeking advice from other 4 owners on what other upgrades are recommended.
I have Jerry Hatfield's older book on fours and wonder if following his advice is sufficient?
Mahalo (as you might have guessed, I live on an island with no other 4 owners around)