I am putting an 89 hatch (red) in the local demolition derby. Too much bondo. Spun bearing. Engine dismantled by the previous owner. No big deal, it happens. Bought another 89 hatch (silver) for $50. Third cylinder was dead. About 15% of an exhaust valve was missing. Again, no big deal, it happens. After I made sure the first (red) head wasn't siezed, I put it on the second (silver) engine. I figured may as well I have a running engine before I go any farther. I dropped the exhaust manifold and left it, the intake manifold and left it, set the distributor and the two sensor wires under it, timing belt, and radiator hose aside. Installed the red head onto the silver block using the silver head gasket and some Permatex (black, if it makes a difference). After I timed it, I turned it over. It cranked a little while, and when it started, it went straight for the redline. I shut it off. Gas pedal wasn't stuck, and the butterfly valve wasn't stuck and moved with the pedal. OK, I can accept that it happens, but I can't understand why. Other possibly pertinent information: I had someone else start it while I held open the top butterfly and could see fire beneath the second butterfly while it was running. I touched nothing else other than what is listed here. Why is this happening and what do I do to fix it?