i have a phase2 2.5 block that i could just drop in between the 1.8 heads and have a higher comp 2.5
i have a rotated turbo kit setup i could stick on the 1.8.
or the 3rd option i've been toying with (but i have no $$ for) is drop some STi pistons and rods into the 2.5 block and put the rotated setup on it with a vf39 or something similar (not really feasible but it would be fun as hell

all would be run off of the 1.8 ecu with a greddy emanage blue.
so... what do you guys think?