I know this has been around for 8 years, and I have the same question today: is it better to go with aftermarket aluminum *(al la www.440Source.com) or find what’s become a bit of a grail in a set of unmolested 915 heads offered for a single year 56 years ago. If I were racing, and to fit into...
Not all of them are. There are many 440 blocks from later years installed in trucks and motor homes with cast cranks, and they are all as viable to build, if not more so due to casting improvements, than an RB block from the earlier years.