installing distributor

[bigdawg]

broke the rotor by putting cap on c*ck eyed and took it out put a new rotor but my question is if i line up the harmonic balancer to timing cover number "0" can i be 180 degrees off TDC? double checked wires there all in correct firing order, checked spark and have it but im backfiring like crazy for some reason car ran a week ago so i doubt its carb

350 chevy motor

 

[pontiacgp]

it sounds like the distributor is 180º off. The crank is at zero twice, on a compression stroke which is what you want and on an exhaust stroke