I pulled my engine to replace a lot of parts... I replaced the timing chain i made sure the crank and timing sprocket where dot to dot before i pulled and installed the chain, then i installed the new cover and new water pump... installed the harmonic balancer and pulley... The two marks on the harmonic balancer are pointing at the two locations on the timing cover tabs like they should... i poked in my distributor and was able to get it with in a few degrees of the 6 cast on the base of the distributor which is firing at the #1 plug on the cap (i followed the EDI Engine Timing thread on this forum) however iv done a few sbc v8s normally you have to rotate the engine another 180* from dot to dot so the cam sprocket dot is on top towards intake manifold but still on a vertical plane relative to the crank sprocket dot then poke the distributor pointing at plug #1 on the cap? Right now im assuming my distributor is off 180*?

Any help would be great thanks!

 

When the timing marks on the harmonic balancer are lined up with the marks on the timing cover, #1 piston could be at TDC on the compression stroke, or TDC on the exhaust stroke. If they're lined up on the exhaust stroke when you install the distributor, the engine will backfire while cranking, and will not start, (distributor is 180 degrees off).