I have a 69 camaro with a new professionally built 454 engine, i put an HEI distributor in it, i ckecked the timing,pulled no.1 brought it up to TDC and dropped in the distributor, number 1 on the cap is the first terminal at the connection box, I have seen some that no. one is the second terminal in a clockwise rotation. I have checked all plug wires to make sure they are at the right plug, the cars runs rough and wants to back fire especially when first started up, could there be something in the distributor causing this, i am stumped at this point, help please. The car is running a Edelbrock 750 which is new and timing is set at 10 degrees.

most likely the timing is not where you think it is, sounds retarded, a lot. Have someone else fire it up while you have your hand on the vacuam can. soon as it fires, yank it toward the carb till she smooths out. Once it's stable, reach for your timing light.

You can also cold time it
1) roll it over with #1 plug out to just before TDC
2) set timing by rolling motor over by hand until timing marks line up
3) turn on key with screw driver in the end of the #1 plug wire.
4) hold screwdriver next to block (1/4 inch away)
5) turn dist until you see spark jump from screwdriver
6) back dist up just a hair and tighten it down
7) Put the plug back in and wire
8) Fire it up and time it with a light

Check the fireing order and #5 and #7 plug wires. These two are very easy to cross.

I agree with Jim, the timing marks may not be accurate or your distributor may be off by one tooth. Also make sure you are setting the timing with the vacuum advance hose plugged if so equipped. I would set it closer to 12-15 degrees. Double check correct distributor installation first.

I received a rely from Jim M regarding my timing and did what he said by starting it and turning the distributor until it ran better which worked, but now my timing mark is about an inch past the scale on the damper, what does this indicate, distributor off etc?

Could mean the harmonic balancer has slipped or the balancer / timing indicator are not original and don't line up like they should. Sounds like you need to use a piston stop to find the true TDC and put the appropriate size degree tape on the balancer.