Michael
All I can add is as follows.
Replacement blocks had no numbers from what I understand, and for normal stuff you could only buy block and piston or engines. LJ XU-1 may have been different as the blocks were not cast by Holden (so possibly could have been supplied outside of Holden?). CAC cast them using a different cast material. This applies to both JP and NP prefixed blocks. There have also been a number of NP blocks turn up with an odd R on the engine pad which normally indicates a repeat number, but on these its in the wrong spot and seems to frequent - ive yet to nut this one out. Police numbers as far as Iunderstand were only issued when you went to register a vehicle.
I think youll find why the JP blocks youve seen with later numbers than the casting dates indicate is because the blocks were cast in batches by CAC and used later. Same happened with manual HQ 350 engines. These all are very early cast and US engine numbers but have Holden engine numbers up until HQ manuals finished. Nasco/GMP&A blocks for XU-1 probably would have been the same.
Any replacement engine sold by Nasco for LC XU-1 would not have been JP, JP was only fitted to production LJ XU-1. NK prefix is what would have been sold for LC XU-1 post HQ engine production. Im not sure what any replacement engines sold prior to HQ had on them (never seen a single one of any description). Holden would have kept some NK engines to cover LC warranty, but after that as you say 202s would have been sold (with NP) for LC XU-1 replacement. Nasco/GMP&A engines sold post HQ but for pre-HQ vehicles with non-HQ sumps had prefixes like 186N, 308N. There was no need for a 3100N as NK existed.
Remember QL, QT etc blocks had neoprene rear mains up till some time around 1973/1974 so Q/J/G etc series numbers would have reached Qx500000 or thereabouts by that time. Nasco probably kept some neoprene block and piston kits for neoprene crank engines, but most sold were probably engines so youd just get a rope seal engine to replace the buggered neoprene engine.
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If we all had the same (good) taste, who would buy all the Fords?
Edited by user Wednesday, 13 May 2009 11:11:45 PM(UTC)
| Reason: Not specified