Need help with my 4th gen

[rboyer]

I have an 86 celica gts with the 3sge motor which has been sitting around until just recently when i scraped up the money for a bottom end to put in it. I got the thing running a few days ago and it seemed to lack bottom end power on acceleration, but had decent power in the top end. I suspected that something was wrong with the tranny and that maybe the TC was trying to lock up a little early or something and tonight i decided to drain the tranny fluid, pull the pan and change the filter, then top it off with new fluid and right after i did this i finished off by finally putting the exhaust manifold heat shield back on which i failed to do when dropping the motor in due to a combination of being impatient and lazy at the time.. when i finished i took the car for a test drive for a couple of miles and noticed a knocking sound and total lack of power.. i pulled in a parking lot and checked it out and it was idling around 5-600 rpms and didnt make any odd noises at idle.. while applying a little gas i could hear the sound and it sounded more like it came from the top end.. after hearing the sound i noticed two things... my radiator was bubbling over a little like it was on the brink of overheating and my exhaust manifold was glowing like a nuclear power plant that just went into meltdown.. i shut down the motor and pulled the temp sensor plug temporarially so that the fans would run full time and the radiator calmed down like 10 seconds later, but what worries me is that the exhaust manifold being red could possibly be a sign of a clogged catalytic converter?? in my head that kind of explains the lack of low end power, but i could be wrong, and also that knocking sound coming from the top.. it sounded like the cams and kind of sounded like the noise they make when a car overheats, but my temp gauge wasnt even near the red mark and that still doesnt explain the total lack of power that i got all of a sudden. i was reading some posts about people with red hot manifolds and the answer to their question usually depends on who answers it from what i've seen, so i figured i would be as descriptive as possible and also if it truly is rod knock then i'll be selling an 86 celica gts for parts because all of the time i have just wasted on the bottom end that i put in there is time that i could have been doing something more worth my while!

[toyomoho]

Did the engine run cool before your parked it?

A badly plugged converter can cause engine overheating. You can use a vacuum gage to check for a plugged exhaust system. Or drill a small hole and put a pressure gage in to check back pressure. Or see how the engine runs with the converter off.

A red hot exhaust manifold can also be caused by a lean fuel mixture.

What kind of knocking sound is this. A dull thud, engine knock from preignition. Rod knock is a deeper sound coming from the lower part of the engine. Is your timing OK, did you line up all everything thing (cam and crank) when you put the car back together?

Is your pressure cap ok? The radiator runs under pressure and will boil over if you have diffective cap. Maybe your fan switch is diffective and should have come on without your help. Plugged radiator?

I suggest you go back and look over every thing in the engine. Maybe you missed something when you put it back together.