yeah I just read up on this very same topic on another forum.
The 2jzgte block is three inches taller than the 1jz block.
when you make the stroke longer and use the same connecting rods It raises the position of the piston at top dead center.
here...
http://www.supraforums.com/forum/showthread.php?t=267680
no use typing all I know about the subject while its right there!!
long story short your better off getting a 2jz bottom end.
maybe a full 2jzgte, because I believe I was told that the Heads are completely different, but I dont know.