Help!!

Ok here is the story, I have a 2001 z24 automatic just put another quad 4 in it with 70k miles on it the last one slun a rod bearing!
Coming back from the beach i heard this clicking noise coming from the engine compartment. I let up off the throttle and it quit, when i got back on the throttle it started again. i paid it no attention and was just goin to limp it home. well about 30-45 seconds later the rpm's started going down and loosing power so i shifted it down to 3rd to get the rpm's back up but it did nothing when i shifted to 2nd it took about 5 seconds for it to catch. then i went back to after about another 5 seconds it went back to loosing power so i started to pull off the road and when i did it cut off and now it will not crank it will turn over all day long but wont catch.
I did a compression test on it and the middle cylinder's are dead the driver side is like 65 psi. and the pass. side is like 105 psi. I looked at the timing chain and i don't think it jumped timing it not broke. but i think the reason for the compression is the head gasket.

Any ideas. everyone i ask dose not know anything about these cars!!
:banghead:

Could be a HG or if the motor was sitting for a long ass time without rotatation the rings could have rusted to the cylinder wall and now are completely shot.

Both are possible. But if something was clunking, I would rule more in favor of the rings being fried. Tear her apart and let us know.

well see the engine swap had alread been done for about one month or so, so if there was a problem with the motor sitting for a while don't u think it would have showed up in the first couple of days?? and (it was a noticable click real fast but when u let off the throttle it stopped and came back and get back on the throttle and it would come back....