Ok heres the long story...I finally got my car running the way i wanted it to. 77 camaro sbc 327. Headed up to Sac Raceway for a test and tune session, threw some 110 in the car and popped the hood to do a nuts and bolts check. Turns out my blower belt was riding on 2 of the 10 ribs (weiand 144). Anyways, I ran the car to see what the problem was and it appeard the harmonic balancer was moving slightly. So I let the car cool, grabbed my socket and started to loosed the crank pulley bolt and it broke off. Well after weaping to myself for a while my buddy helped load my car on his trailer (which is when the lower valence got smashed off). The next day upon examining the crank and harmonic balancer it appeard that the balancer was loose previously to me buying the engine. The engine probably has less than 1,000 miles on it. There was no visible damage to the crank and the only damage to the harmonic balancer was on the keyway, where it looked as if it was the only thing holding it on. So I measured the crank and it came out to 1.240 and the balancer was 1.245. I talked with ATI and they would have to make a custom balancer to fit this crank (over 500 the guy said and 6-8 weeks for delivery)...With the crank being so small was it machined when the engine was rebuilt? Does anybody know where I can get a balancer that size? And lastly how would you approach your mechanic who built this engine and did not catch this?