Hi Gang,
Today, I removed the turbo and exhaust mainfold to replace gaskets hoping to get rid of a very odd buzz in the exhaust.
Below is my surprise.

Anyway, my question is will an exhaust manifold from an S5 TII engine fit on an S4?

(I'm assuming that y'all agree this one can't go back on the car).

Here's the page with big pix: http://www.kkoop.com/RX7/EXH.htm

 

they are always cracked, its very rare to find one uncracked. and as far as repairing it, it is very hard to repair iron cast. you need to preheat the metal and weld it with a high nickel filler and the slowly cool it down. i'd just rock it unless you can either find a good one or go aftermarket

 

Find a local welding shop that is confident in doing cast iron repairs. You would be hard pressed to find an exhaust manifold that is in better condition than the one you have.

 

JB weld to the rescue!
I'm sure there are other substances that'll do the trick too.

(Put it on the outside so that it doesn't go into the turbine if it breaks off.)

 

Yes, however you would have to use the S5 turbo. Manifolds are interchangeable between all 13B's, but you need the same series turbo for same series manifold.

 

Waffles waffles, buy tastey waffles...