Stanger85

I have recently rebuilt a 302 carb engine. It is pretty well stock very mild cam and a set of Keith Blackman pistons that I got a really good deal on. The pistons are 8.6 to 1 pretty close to stock (flat top). The carb is a 600 holley, intake is performer and everything else is stock. No matter what I do I seem to get a ticking pinging kind of noise. When I lower the timing I get a noise like someone thumping on the floor pan. I've done everthing I can think of I have taken timing out put it in higher octane gas, checked to make sure my balancer has not slipped, made it run richer and leaner, checked oil pressure checked rockers made sure they did not loosen and where getting oil. I had my distributer matched to my cam and nothing works. Need some ideas, did I miss something or maybe put something together wrong. Also in park running I have no problems sounds awesome it only happens on hard acceleration.