cousblake11

I have a 83' c10 I bought not to long ago and I'm trying to get it running better, it has the newer style 350 with center bolt valve covers, not the vortec engine, with a turbo 350 trans, it has a stock intake with an adapter of some kind for a Edelbrock 600 4bbl carburetor, timing was 20 degrees off so I set it perfect, changed the oil, spark plugs, cap, rotor, ignition module, fixed some vacuum leaks, new fuel line, fuel filter, air filter, tranny modulator, and even put tall valve covers on, after I changed the timing and messed with choke it drove perfect, I changed the distributor cap and rotor with a MSD hei cap and rotor, and got a O'Reilly's ignition module and now ever since I changed it, it starts up perfect and idles good but when I go over half throttle I cuts out, backfires and almost dies, I can't go over probably 50 mph without it doing that, can anybody help me I need this truck running right again so I can drive to work instead of bum rides, any help would be appreciated, Thanks Blake