I have a 1984 camaro i just bought. Had a full exhaust put on it because the previous owner toke it to just headers. now that it has been completed i can hear a loud rapping/ticking noise that was a little intermittent coming from the enigine. the noise picks up speed with the rpms. After driving a few miles it became a constant noise.
I have no idea what to look at for this, what direction to start? Other than someone mentioned a wrist pin.
Any help would be aprreciated.

 

Could be one of a few things..
1. Exhaust leak
2. Lifter Problem
3. Wrist Pin Issue
4. Rocker Problem
5. Rod knock
6. Injector
7. bent pushrod

Did it knock before it took it to that shop? If it didn't, I would suspect an exhaust leak but even that isn't 100% foolproof. Something could have gone wrong with the engine afterwards.

 

I do not know if it did before the exhaust was put on i could not hear anything over it running straight headers. It was the shop that told.me about it before i payed they discovered it when they did their check for leaks in the new exhaust, which was just finished today

 

You could get an automotive stethoscope from a auto parts store fairly cheap and try to narrow down to see if it is external and where it is.