I would love a 2ZZ but there are fitment issues with the motor. Some Euro company swapped one into a Vitz but had all sorts of firewall issues. It's a lot of custom work.

I've heard on various Scion forums that some guys are currently swapping in a 4AGE, so that's also an option.

I still think the 4E is the way to go. With minor upgrades, they can easily make 180 whp, and I wouldn't have to rev the thing to 6800 or so like the 2ZZ just to make some power.