The 3S guys in the US tend to use 272 intake and 264 exhaust. This is based mostly on some opinion pieces posted by Chris Karthage from Engine Logics.
The idea is that the 3S exhaust ports flow extremely well and the smaller exhaust opening time allows more charge to be "caught" in the chamber. What I have seen of the 2J's in the US they tend to run a bigger exhaust than intake cam though.
Take this with a grain of salt, the 3S info I know for sure the 2J info is just what I've seen around the place.
The guy on SF that was talking about the reverse stagger setup did mention 3s's and also 2j's. I will see if I can find his name. He is a prominent engine builder over there.
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