So I've got an '89 745 with the turbo 8v engine (B230FT?). I bought the car with an exhaust manifold leak, and since replacing the exhaust manifold gaskets (and putting a heli-coil in the #3 sparkplug socket) I managed to break a downpipe stud and possibly strip out an exhaust manifold stud (into the head) while working on the car. My present thought is to go to an (almost) local junkyard and pull the head off of another 740 turbo (all of the 8v 740 turbos have the same head?). Before I actually go and do something so drastic, I need to ask about the specifics of the head interchangability:

(1) What range of 8v heads would work with my '89 740? I assume 940t head would work too? What about the non-turbo heads, are they the same, or are the compression ratios signifigantly different?

(2) Also, I never really got the exhaust manifold off. Rather, I was able to pull the manifold away from the head, but then there was one oil line that went around the mitsubishi turbo that I couldn't quite get to loosen. How are the oil lines dealt with when pulling the head? Does one just pull the whole head with the turbo still attached and then separate the exhaust manifold from the head on the garage floor? Does the turbo oil supply line unbolt from a convienient place (on the block)?