Well, I think I have a problem, here there is more slack than I said, I will try to put a small video, but I think I have a slack of about 0.03 "

I can't publish a video

Where are you measuring the bore of the pulley?  The pulleys are counter bored oversize for a short distance on the inboard end.  Measure your bore on the outboard (front)  end of the pulley hub.  I think you'll find a better fit there.  I think the overbore is to make it easier for the assembly line worker to align the key with the keyway.

John - "The Hoosier Hurricane"

that measurement is inside the pulley, I have not measured the outside there is more complicated, I did not know that the hole was conical, I will try to put it upside down and check the clearance, thanks

Capelo.  I watched the video you sent and the video really does not give an idea exactly how loose the damper is on the shaft.  Having fore and aft movement simply tells me that there is clearance between the damper and crankshaft snout but not how much.  You are back to doing some real measuring to get a better feel for determining exactly how much clearance between those two parts exists.  When checking the crankshaft snout, make sure you measure it in several spots along its length to insure it is uniform in measurement along its length.  Likewise do the same for the damper.  As John mentions, the damper does have an increase in hole size at the entry end to aid in the installation on the crankshaft.  What you don’t want is ‘wibble-wobble’ on the damper once it’s installed all the way up to the lower crankshaft gear.  Tightening the damper will ultimately correct for some of the looseness you are experiencing.

Lorena, Texas (South of Waco)

I have measured the crankshaft snout at three points, inside 1,230 "in the center 1,2299" and outside 1,2295 ". The pulley could only measure the inside with 1.25", I have no way of measuring there, I have tried to introduce the pulley upside down and it shows that it enters fairer. The slack of the video is without tightening the screw once it clears disappears when pressed against the pinion of the distribution, what catches my attention is the ease with which it enters and its margin before tightening the

Short of taking it to someone with the right tools and paying them to measure it, an inside dial caliper will get a pretty accurate measurement and pretty cost effectively, as far as precision measurement devices go, particularly for smaller measurements. There are digital versions, if you prefer that.
I have one of these for about 3/8" to 1 3/8" and it's off by about .003" from end to end.  I don't know if that's just the nature of all of them (error in converting angular movement to linear) or simply mine being a cheaper Chinese make.  If you use a micrometer to check and adjust it for the desired measurement, it will be accurate.

Link to an example.  There may be cheaper options, search for yourself:
https://www.ebay.com/itm/SPI-3...

72% of original size (was 703x19) - Click to enlarge



Lawrenceville, GA

Thanks for the idea, but I can't find a meter yet at a good price, it will be better to find where to take it to measure👍

Capelo.  I have twelve Y crankshafts sitting here in the shop from everything for a 256 to 312 engines including a steel crank for a 292.  The crankshaft snout measurements for those ranged from 1.2486” to 1.2504”.  I also had four dampers laying loose here in the shop and the hole measurements not including the enlarged register that aids in starting the damper on the crankshaft ranged from 1.2490” to 1.2499”.  Based on this particular set of measurements, the interference fit can be as tight as 0.0014” while the other end of the scale can have the damper as loose as 0.0013”.
 
Of not any consideration in regards to how tight the damper is on the shaft, the enlarged portion of the damper holes (register) ranged in measurement from 1.2685” to 1.2740”.  Those enlarged registers are about 1.300” long before getting to the portion of the damper that actually dictates how tight the damper will be to the crankshaft snout.

Lorena, Texas (South of Waco)

Thanks for the contribution, harmonic shock absorber may not be too far from these measures, but I'm still waiting to find who fashion the outside