thanks for your responses, was just trying to get my head around it being marked out to 30 deg. .but Ted  did that well.  Thanks again.

Melly… I sure wish miss mine was that plain to see. After getting back being rebuilt I had to file in where the marks were. Make sure you paint all the lines white. It would be ez to make a 40* mark now that it is off.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Not sure what you are asking.  The pictured damper is marked in 2° increments with the numbers being at 10° intervals.   Most oem dampers are only marked up to 10° but it's not unusual for aftermarket dampers to be marked out further.  The ATI and Innovators West dampers that I use are marked the full 360°.  For the stock dampers, I typically add a 35° and/or 38° mark on the dampers so I can set the total timing at the increased rpm that all the distributor timing is ‘in’.  Depending upon the distributor, that’s usually between 3000 and 3500 rpm.  Iron heads typically prefer more total timing than the aluminum heads so any total timing marks I add to the stock dampers takes this into account.

As with any damper, it’s important that the zero on the damper coincide with the true TDC of the piston.  The factory spec for the TDC mark on the damper is for it to be 107° clockwise from the key slot in the damper.

Lorena, Texas (South of Waco)

Can someone explain the timing mark on this. Shows 10– 20 —30 .

... the 57 dizzy does not use the clip and modifying the rotor is needed with the petronix installed.  Still I wonder if the loose fit on shaft would still be a issuse ...

Does the rotor tip hit the cap points at all? If not, it may be the rotor itself.

It's getting harder and harder to find quality parts.

Either STANDARD IGNITION or NOS IMO.

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So being the 57 dizzy does not use the clip and modifying the rotor is needed with the petronix installed.  Still I wonder if the loose fit on shaft would still be a issuse 
But I am learning alot as always great source for help and great group of great people will to help. 
>

Yes I have a Petronix !! installed

Hot rodding improvements are so much fun.
The instructions say just install, one size fits all, need no modifications, bolt is..etc

56 Vic, B'Ville 200 MPH Club Member, So Cal.

... the rotor seated on the reluctor ring and prevented the rotor from seating on the shaft.  The result was that the rotor hit the terminals in the cap ...

...hmmpf ...

THANX! for that info!

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