Quote Originally Posted by firebird77clone View Post
This brings up a point I've often wondered: just how important is the almighty zero?
Just like anything you measure, the value you measure only means something if you have a known, repeatable reference point. If you're measuring a crank journal does it matter if you zero your micrometer before you measure? Timing's the same, and accuracy of your zero point (or of the other 359 marks) is pretty critical to anyone else that tries to make sense of that engine's settings at a later point. With today's crappy fuel and more exotic materials used in performance engines timing can be even more critical. For example, the hypereutectic pistons in my 347 came with a strong warning that total timing is not to exceed 36 degrees, which became the limiting factor in building the timing map for computer controlled spark advance. Other sources say that pushing total timing to 40 or more as you're pushing the rpm limit will squeeze out more power.

Does all of this apply to a near stock 350 SBC engine? It's not necessarily "critical", but like Jerry points out if you have ANY unknowns like timing cover, placement of the pointer, etc, etc, etc, then knowing your zero point is, to me, one of the basics of knowing what you've got. Anything less than dead right makes it a crapshoot.