I am at my buddy's machine shop and he is balancing my 400 crank.

We slipped the Edelbrock Performer double-roller timing set crank gear for the timing set on the crank snout...the crank snout is undersized below the leading edge of the snout. There is a tight fit when the gear initially slips over the snout, but then once the gear gets past the majority of the key, it has some slop where it sits on the crankshaft.

Is this normal, IE will the damper hold it in the proper location once we tighten the harmonic balancer bolt?

 

Should be a "slip fit" will no "slop".

 

Mine was the same way. Makes me nervous.

 

As an old fitter and turner, Slop is very subjective.
Size for size can be very tight and a mongrel to get on and off. You will find harmonic balancers will be at least size for size and a little tighter for good measure. Interference for most things was always a thou for every inch in diameter, and running clearance for bushes etc. the same but the other way if you know what I mean.
There are a lot of charts out there for tolerances and slips/fits but these were the benchmarks for most general fitting and all the tolerances were usually for mass produced items to allow for minor variations, otherwise they would have a lot of failed items.
In a small shaft like that crank snout, and while I didnt measure it when I did mine, that snout would not be more than 2", I would suggest that it probably should not be anymore than 0.001" clearance. The bearing surface of the gear is pretty much square so that does you no favours either. 1 thou clearance on a gear only one inch or so wide feels a lot looser than one 3-4 inches wide.
If really concerned get your machinist to measure the snout and the bore on the gear and actually see what the clearance is.
I would also suggest if it was close that the harmonic balancer, when tight, would also retain it.
Maybe some-one out there has been caught or knows what the maximum tolerance is.

 

Alright, we got it figured out!

We had overlooked it, but there is indeed a bevel or taper on the crankshaft where the timing set small gear meets the crankshaft. There is a matching bevel / taper on the timing gear. When you press the damper on, it creates a perfect fit where the tapers of the timing gear and the crank mesh and the gear becomes perfectly centered. It is a strange design, and my buddy who is most familiar with Chevy, was not impressed with it, but nevertheless it is effective!

 

Good to know. That makes me feel better about mine.Thanks