![](/profile/get-photo.asp?memberid=234&type=profile&rnd=164) Shaftsbury, Vermont (SW VT) | Yes, there were two 504 blocks. I can't remember now how to tell before teardown, but BDT or something like that in the info on the engine tag comes to mind. Heavier crank in a 1370, and I think that's the BDT one. Difference in the diameter of the main and rod bearing journals. Hope this helps; someone else may join in. OD |