new Heads?

[mannasugar]

92 RS Camaro fixed sort of , I originally said the “Security light” went off, it went off because the the pass-key module was reading the correct resistance (ohms). I unplugged the ECM and now the car starts 99% of the time, and now I know that there is a 4 minute delay, so I can now drive the car without being stranded.
I got this car for $800. The car had 2 problems that allowed me to get it so cheap. 1) the VATS problem 2) the coolant fan does not work, it works but not on its own, I have a jumper wire hooked to it, and of course one day I forgot to hook the wire up and the car overheated, it got to over 160 degrees, a couple of days later the car started to run very poorly, I think I have a dead cylinder. From a vacuum reading I am getting about 18 psi which fluctuates 1 to 2 deg. After increasing the rpm to about 2000 rpm. There is no coolant/water in the oil, I squirted penetrating oil in the carburetor and there is a small amount of smoke coming from the #1 cylinder. The spark plugs are so difficult to get to, I can't really get a compression test. The car is missing so badly that power is cut by (guessing) 60%. The fuel mileage has also been cut by 30%-40% again an estimation. 3 days ago the car had plenty of power!
Where can I find the best bargain for Heads?
Is the salvage yard a good source?
Should I buy used Heads or new Heads?
What is the best diagnostic tool I can purchase that will not kill my pocketbook? A diagnostic tool that will supply information such as engine performance.
All replies are appreciated.
Thanks to everyone.
D.J.

[72chevelleOhio]

Originally Posted by mannasugar

. The spark plugs are so difficult to get to, I can't really get a compression test..

And putting heads on it will be easier and/or cheaper because.........?

[Morley]

The "best diagnostic" would to perform a leak down test and to check that all cylinders have spark. Throwing parts at it is not the answer.

[wrightz28]

How did it "overheat" at 160*?

Also, be careful with your wording, unless you have a mutated engine & management system rendering any advise from anyone useless wiithout knowing, you don't have a carb as they were no longer a option after 1987.