Just wondering... if 2.5l+ is more common with atmo YB:s, a slight compromise in piston height and/or rod angle might do the trick, with what's essentially an identical recipe. Modern dry liner alu blocks might be able to withstand abuse quite a bit better than the YBD could. Then again, I gave it absolutely no mercy so no wonder it blew up, with by far the most spectacular smoke screen I've ever seen an engine make. My later experiments with Nissan RB tall deck strokers have turned out great so it would be a shame not to use the same principles with the venerable YB.

We'll see.