engine on a 69 gto

i have a 4 barrel and the engine keep backfiring. does any one know maybe around what the timing should be set at and how i should tune the carb? any help is appreciated

Nice car, but to own a car like this one would think that they would have the basic specs to keep it running right, anyway go to allpontiac.com for some info.

10 degrees initial and 36-38 in by 2500.Check the valves for proper clearances.

But check TDC FIRST!