MSD Rotor Phasing

[70L34]

A post on another board jogged my memory on this topic-

I have a locked out MSD Pro-Billet controlling a B-to-B FAST system on a Pontiac 455. Crank reference angle is 50deg BTDC. I assume that implies the reluctor tab is directly centered at 50 degrees. However, I never did measure the rotor phasing. Am I to assume that there could be a problem with spark scatter when the timing is delayed down to 15-20 degrees? I take this to mean that the rotor tip is now 25-30 degrees away from being centered on any wire terminal when it's fired (assuming the "lockout" feature lines the reluctor wheel up with the rotor terminal).

Just curious if I have a potential problem on my hands--thanks!

 

[Craig Smith]

Yes, this is a potential problem. The solution is either a phasable rotor setup from MSD, or rephase the reluctor wheel on the distributor shaft so that you can have the rotor phase and reference angle correct at the same time.

Some folks get away without doing this, but I would recommend addressing the issue. Spark scatter = bad.

 

[70L34]

Thanks Craig,

Do you know if I can just replace the rotor with a phaseable unit, or if I have to switch to the Cap-a-Dapt kit (cap and rotor)? That would force me to buy new HEI-terminal plug wires, which I'd rather not do. Thanks for the help. BTW, Todd was very helpful with my WOT tuning help when I spoke with him a couple of weeks ago. You have some talented people working with you.

 

[Craig Smith]

The phasable rotor only works with the cap adapter thingy. Could you just crimp new ends on the wires if you went this route?

The other option is to relocate the reluctor wheel.