Misc 2L questions

[ydrogs at gmail.com (Gordy Stedman)]

Not to hijack this thread but I have some 2.0L questions myself. I have in
my shop a 3A 2.0L block, JH 1.8L block, PL 16V 1.8L block, 1.8L hydro head,
1.8L mech head, 16V 1.8L head all sitting next to each other. Except for the
alignment pins set in the blocks what is stopping me from using the 3A block
on any of these heads? There has to be a reason no one runs a 3A with a 16V
head. Using the head gasket as a guide it looks like all the water and oil
jackets line up and the head bolts are in the same spot for all these heads
and blocks. I know the 1.8L heads have the one round opening sealed up but
all the blocks have it open. I am guessing it has to do with the stroke of
the block and the related compression ratio but that can be changed. Is the
9A 2.0L 16V block the same as the 3A bubble block? No one who uses the 9A
seems to have any hood clearance or exhaust alignment issues like people do
with the 2.0L ABA tall block. I am just trying to make sense of what is
really swappable between all the different top and bottom ends. TIA.

--
Gordy
MK1 x 3
MK2 x 1