i dont think a msd pro billet can bephasing a distributor just means that you need to make sure that the rotor tip is lined up properly with the contact in the distibutor when it fires, that is , pointing directly at it.to check it , put the timing pointer on 38, then take off the cap to see if the tip is aligned exactly with the dist. contact. if they aren't, you need to turn just the cap or "bowl" like on a msd pro cap. don't turn the whole distributor, or timing will change. not all distibutors can be phased, as the cap can't be rotated independently.hope this helps
This is the way I do it. Old cap with a hole cut in it, spinning on an old distributor machine, using an MSD adjustable rotor. It's my understanding that you want the rotor tip on the "leading" edge of the contact.I used to get an old distributor cap and drill a hole in it, then use a timing light throught the hole to check rotor phasing. The MSD rotors have slots so they can be rotated to get the tang lined up perfect with the cap post. Or at least they used to be 2 pieces.
Thats what I've been told too....but where do you set it if you run 6* retard with a 250hp Nos shot ?This is the way I do it. Old cap with a hole cut in it, spinning on an old distributor machine, using an MSD adjustable rotor. It's my understanding that you want the rotor tip on the "leading" edge of the contact.
guess they dont have this for a chevy cap??if u have a worn cap/rotor on your 85551 distributor, this is perfect time to upgrade to this....
drill a hole by number one terminal and when setting your timing with a non advance gun, shoot in hole u drilled in cap and the rotor can be adjusted for the arc to be hitting on the trailing edge. so when you use nitrous and want retard it will be arcing from center of rotor terminal to center of cap terminal...i love mine !