Setting the advance curve mechanically on a MSD

[pipnit]

Anyone have any thoughts on changing the curve on an MSD distributor? I think Stock, they're setup to hit full advance at 4,000. I was thinking of changing it so that it's full at 3,500. Anyone have any actual experience with doing this?

[maddad]

Yes, it's done with bushings to limit the amount of advance(larger is less) and springs to control the rate(lighter springs advance quicker).
The largest bushings allow 18* advance and the lightest springs have it all in by 3300. I use 14* initial plus 18* for 32* by 3300rpm.

[justleft]

My 454 is 26 degrees total all in at 3500. I know I'm leaving some hp on the table but it gives me some slack
on octain.

You can buy the little bag of springs and bushing kit for about $15 from Summit and others.

[pipnit]

Thanks guys! I went ahead and set it do full advance at 3500. The problem is the "box" is back ordered nation wide right now. That's OK, my MERC one is working fine, just don't have a rev limiter on it. Thanks again...