I recently changed the clutch, disc and all relevant components, took the engine out and put it back. I noticed that the engine bay gets too hot and the car is not comfortable reving beyond 4000 rpm, the engine seems to start to veer a bit to the left side and the sound of a screaming belt is heard at the alternator pulley.
It is almost as if the engine is not settled properly in original place. My rx-7 is a 1981 model

 

Does it seem like it redline at 4k? I had this problem and it was my trailing or leading coils coils were bad. Idr which is which right now but the coils between the shocktower and fire wall. Bought a used set on ebay for like 60 bucks and it fixed my problem.

 

 

It is not a fuel or electrical issue, I have a feeling that the engine is not been put back correctly. That is why it kind of veers to the left side and the alternator pulley produces a screaming sound as a result of that..

 

You should post some pictures or a video, so these guys have a better understanding of what you are asking.

 

I managed to solve the problem, the screaming noise was from faulty bearings in the alternator. And the low revs from fitting the vacuum pipes from the carb to the distributor in the wrong order. the advance in the trailing and the trailing in the advance. Its working fine now.