i have no clue if there is such thing as a "exause" ..that has got to be some creative spelling! I think the word your looking for is Exhuast...as far as the "stock" size ... All i know for sure is oversized valves are 1.59 exhuast side..so something smaller than that
i have no clue but i do have a brand new complete head with bolts and gasket that might work for you if you are looking for one it is for an 80 never been put on still in the plastic and covering they put on it from the factory wanna make me an offer on it? plus i have a bunch of other stuff for an 80 coupe 4 bangaer car including brand new red interrior. P.M me if you are intrested in anything i'm bascially gutting the car to put a 5.0 in it to race. all the interrior is in mint condition and it's all got to go.peace john