I hesitate to post on a "race" forum but here goes. I have a early Siamese block (2000) Callies 4.5" crank, 4.375 bore, 10.75 comp with port matched MP aluminum heads. Cam is .246/.254 @ .050 .585 net lift on 112 separation, solid roller. Stage V intake with (2) Holly 750 carbs, TTI 2" headers. We dynoed the engine and it pulled 635 HP @ 5900 rpm. BUT when I got it home and installed in the car, it didng't feel right so I checked TDC with a piston stop and checked against the tab where the engine builder set the timing. Care to guess? it was retarded over 10 degrees! They dynoed it at 32 degrees? I put a vacume gauge on it, set the initial, welded up the advance slots etc. I am now running a TRUE 35 degrees total and it feels MUCH stronger!
Still runs great on 93 pump with vacume advance bringing the total to 44 degrees under light load with no detonation. Car weighs 4,175 empty, 3,000 stall with 3.54 gear and GV overdrive. Just a street car though. If I was going to race, I would have started 1,000 lb. lighter. Can't beat it though in summer with the top down!