Reverse-engineered and Re-rated Ships?

[Joe C-P]

Coal-slurry might be easier to move, but it adds water weight; how much energy density is lost by this?

Back to the original subject: I've proposed the US chooses to grant independence the Philippines post WW2. To arm their new navy, the US provides mostly small vessels to patrol the many small islands, but also a few four-stackers, and a pair of Connecticut class pre-dreadnoughts. (Japan refuses to accept full battleships being provided, even the oldest models.)
The US then upgrades the vessels up until WW2 starts, at which time they battleships manage to escape to the US, where they are upgraded with modern 12" guns, or perhaps 8" triples, the old 8" twins replaced with 5"/38 twins, light AA, communications, and radar.
They continue to serve into the 60s, the 5" being replaced with single 5" and Sea Sparrows.
The four-stackers also get upgrades over the years - new guns, radio, radar, torpedoes, Hedgehogs, Sea Sparrows or Tartar.

Does this makes sense? Eh. Does it make for cool models? Yes! If anyone ever releases a 1/700 plastic Connecticut class, I will be doing these.

[Hobbes]

Making synthetic oil requires lots of energy, so you end up with an inefficient overall process. Space isn't really at a premium in a warship, so it's only worth going this route if the dust combustion hazard cannot be solved. 

Isn't the making of synthetic oil done on land facilities?  Or am I missing something here?

Sure, it's done on land, but if there's such a shortage of oil that we're considering using coal instead, it'd be dumb to choose an inefficient process which wastes half the coal.

[Weaver]

The four-stackers also get upgrades over the years - new guns, radio, radar, torpedoes, Hedgehogs, Sea Sparrows or Tartar.

Tartar would be pushing it a bit. Post-war all-gun destroyers and frigates that were much bigger than the 4-stackers struggled to accomodate Tartar: the conversions ended up with only one tracker and topweight problems and were generally judged uneconomic.

For an early US refit, I'd suggest a 5" Mk.32 fore and aft and twin 40mm port, starboard. Hedgehog and Mk.32 torpedoes for ASW. Later, you might get ASROC onto one amidships: the JMSDF have put ASROC onto some pretty small hulls.

[Joe C-P]

The four-stackers also get upgrades over the years - new guns, radio, radar, torpedoes, Hedgehogs, Sea Sparrows or Tartar.

Tartar would be pushing it a bit. Post-war all-gun destroyers and frigates that were much bigger than the 4-stackers struggled to accomodate Tartar: the conversions ended up with only one tracker and topweight problems and were generally judged uneconomic.

For an early US refit, I'd suggest a 5" Mk.32 fore and aft and twin 40mm port, starboard. Hedgehog and Mk.32 torpedoes for ASW. Later, you might get ASROC onto one amidships: the JMSDF have put ASROC onto some pretty small hulls.

Would there be enough weight allowance for a full 5" single mount fore-and-aft? Perhaps 5"/25 shielded, or maybe 3" and Hedgehog forward, 40" twins amidships, torpedo twins port and starboard further aft, and some MGs.
How about the Sea Chapparal?

[Weaver]

The four-stackers also get upgrades over the years - new guns, radio, radar, torpedoes, Hedgehogs, Sea Sparrows or Tartar.

Tartar would be pushing it a bit. Post-war all-gun destroyers and frigates that were much bigger than the 4-stackers struggled to accomodate Tartar: the conversions ended up with only one tracker and topweight problems and were generally judged uneconomic.

For an early US refit, I'd suggest a 5" Mk.32 fore and aft and twin 40mm port, starboard. Hedgehog and Mk.32 torpedoes for ASW. Later, you might get ASROC onto one amidships: the JMSDF have put ASROC onto some pretty small hulls.

Would there be enough weight allowance for a full 5" single mount fore-and-aft? Perhaps 5"/25 shielded, or maybe 3" and Hedgehog forward, 40" twins amidships, torpedo twins port and starboard further aft, and some MGs.
How about the Sea Chapparal?

5" guns: I should think so, as long as the sided guns were replaced with something lighter. Remember that the 4" guns are pedestal mounts with separate ammo hoists, so fitting a "deep" turret with a magazine directly beneath it involves making some serious structural changes. You could always leave the shield off the aft gun to save topweight. BTW, I got the name wrong: it was the Mk.30 I was thinking of, not "Mk.32"

A couple of Sea Chapparrals would go well on the sided 4" positions: good field of fire and relatively shielded from spray.

I'd definately replace the 21" TTs with triple lightweights if you want them for ASW capability: saves you a heap of weight and there's not much in the way of Western 21"" ASW TT development post-war (apart from the French).

[tigercat]

HMS Radiant a WW1 design lasted until at least 1957 with the Thai Navy  I don't know what armament changes may have been made though

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