There has been a lot of talk about guys having problems with the 514 crate, and basically had to de-tune them to keep them together. No wonder Ford took them off the shelf and no longer offers them. Hope their new BB is thoroughly tested before offering it to the public this time.
Tom: I know a lot of guys with the 392 crate and like it very much. There were some
oil issues with the early offerings but Ford seems to have solved that - at least in the 430HP version. The intake is pretty much a copy of the popular Vic Jr. and many of the guys I know have experienced a BIG HP/TQ increase by switching to AFR 185 or 205 heads. They said it really wakes the 392 up, adding between 70 and 90 HP.
You may want to give that a try first before going through the expense of buying a new engine and everything it takes to go from a SB to a BB in your SPF.