The 1989-92 stock Mazda cast iron turbo manifold does not crack in
automotive
service, it will fit the gen 3 and it is not that heavy as I recall
because it is small. See the picture below.

Paul, the stock manifold WILL crack. Mine was cracked in the center web
(between each exhaust passage) all the way through, and there were several
severe cracks around the periphery of the turbo side. 1990 T2 car with 166K
miles upon disassembly. I think I still have the old mani; if I do I will
try to get some pics. I might have some pics from when I magnafluxed it.

Mike Harrington

Well apparently I am mis-informed. Is your turbo cracked too Mike?
Not clear from your post.
What did you replace it with? 
Did you own the car from new?
Did you jack up the boost?

Paul Lamar
 
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