Problem Statement
There are two problems. The first problem to arise was loss of power with the engine under load. This only happened when attempting to climb a hill. The problem started from there and got worse until the engine would not run under any load. There were no problems with idle or revving the engine. Just before complete power loss the second problem arose; the exhaust started to leak from the engine bay so bad that it would flood the passenger compartment with fumes. This made the car impossible to drive.

The Car
1982 Nissan 280ZX Turbo – Manual transmission

Theory
Pre-existing exhaust leak allowed too much air into the exhaust manifold causing the O2 sensor to detect excess air. This caused the ECU to incorrectly compensate by adding additional fuel to the combustion process; unburnt or still burning fuel exited the combustion chamber and continued to burn causing excess heat and further destroying the exhaust manifold gasket (based on a previous experience).

Theory Updated
In the process of removing the exhaust manifold, other, more likely factors were found that could have caused the loss of power. These problems are discussed further in the body of the procedure when they are encountered. This is to demonstrate the learning process as I explore a problem that I have no exact previous experience. Also, after everything was removed it was determined that just a little more work and I could replace the timing chain

I started a blog and posted it there. Lots of fun pictures. I am not finished with the project yet.
http://jmkubli.wordpress.com/category/280zx/