Got a chance today to compare EJ22 heads beside EJ25 heads. In this pic you can see rear and to the left, the donor EJ22 JDM motor I got a couple of weeks ago with just under 50,000 miles on it. It looks to be in good shape.
To the right in the pic are two left, driver's side heads....the dual cam on the left from the EJ25 motor and the single cam EJ22 head just out of the machine shop ( but with a dirty old valve cover on it ). The EJ25 head is not only way more bulky but it is 3/4" wider than the EJ22 head. That adds up to 1.5" total width increase across the whole motor and that will not fit between my 29" rear frame rails. The EJ22 is only 28.5" wide.
This afternoon I will level the motor and mock fit both EJ22 heads and check that my intake manifold will fit properly with the existing.060" head gaskets. If they don't I can tweak the thickness so the manifold will fit. I'll order new Cometic gaskets tomorrow. They actually make hybrid gaskets now to properly mate the 25 block to the 22 heads.
