I don’t know what it is, maybe it was just how freakin bad the piston/cylinder fit was, but the old Ford engine would puke oil out of every hole it could find under boost, and it was only seeing 10 psi.
The new engine conversely, using the same stock 40-50k mile pistons with only a hone, and a new set of rings doesn’t huff, or hasn’t left even the slightest amount of oily residue in the catch can at over twice that boost number.
Not to brag up a 2jz, but whatever they’re doing to control blowby, it works.
Maybe it’s the square bore to stroke thing, maybe it’s because of the block integrity, maybe I got lucky this time with my ring fitment.
I don’t know if gapless rings are recommended for a boosted application, you will have to do your own checking into that. I know you don’t wanna do things twice any more than I do.
* I just skip over the “ twice” part, and just go straight to 3-4 times over when having to fix my screwed up sht.