A little more history guys.
It is a base 350 horse GTO engine with old Hooker tube headers. GM HEI distributor that I recurved (weights and spring changed) based on an article in High Performance Pontiac around 1990.
I installed a HO Performance cam called HC-01 ~20 years ago. I installed it myself and I thought I did it in the car. That's why I was surprised to hear the mechanic say it should be removed. But then I thought that maybe I did it before I installed the engine. I would have used the Green Service Manual for reference. Gettin old and senile.... can't remember exact details
This cam has higher lift than RAIII and a higher rpm power curve but tamer than RAIV. I planned to install a higher rpm stall converter to help it run better but never did. I did install Rhodes anti-pump up lifters to help the idle/vacuum smooth out which was rec'd by HO Perf when I bought the cam.
I sent my carb (orig Q-jet) to Cliff Ruggles who was highly rec'd here about 5 yrs back to get it rebuilt and I did that. I thought that would fix the nasty smell. People who have smelled the exhaust said it is running way too rich. We figured it was because the Cam Overlap was too much and it was dumping raw fuel out the exhaust. Since the car didn't get run much, I replaced the gas tank about 7 yrs ago but smell is still there with new tank and fresh gas. I burn 93 Octane from Citgo. Could the smell be caused by the valves not being adjusted right? IT doesn't ping at all when I get on it with 93 Octane Citgo gas.
I think it also lacks in low end torque for a 400 GTO engine. I thought that would be another symptom of having to hot a cam in the car.
I really appreciate all the help. I really want to remedy this problem this fall since the weather is nice to work on & drive the car.