Slight ping.

My 65 Pontiac with new 400 crate motor is out of the shop. I'm getting a slight ping that I'd like to get rid of. Shop guy told me to set it at 4 degrees BTDC. When I did, I got lousy accelerator response. It's back to where it was before but that ping drives me nuts. What can I do. I haven't messed with the carb much yet just adjusted the idle screw because moving the timing dropped my RPMs a lot. It's a 750 CFM Edelbrock. This car is ready to be driven...just gotta get rid of these kinks. See my post below concerning brakes too....I really need help on that one too. Thanks much. I could take this back to him of course but I'd like to drive it this weekend.  

Ya setting the timing at 4 degrees is not even close.
Give me some specs on the engine like type of pistons flat or dish top and the casting numbers on the heads which is located on the center exhaust ports.
Also what type of distributor is in the engine and does it have a vacuum advance.
what is the timing set at?  
professional hi-performance engine builder

Horsepower sells engines and torque wins races

Most pontiac motors are advanced on the timing (I have 12 Degrees advance initial and 32 Degrees Total with the distributor and vacuum advance at 2500RPM). How much compression and what type of fuel are you running?On the iron headed pontiac motors 9.5:1 is about all you can get away with on 91 octane gas.