Originally Posted by 1957willyman
how can i prevent my initial timing and centrifugal timing coming in at sametime my engine idles about 1200 rpms has about 23 degrees timing msd distributor with whatever springs and weights came in it
If you're saying that the mechanical comes in at idle speed, you need stiffer springs. Typically you want the mechanical all in by around 3000 rpm (this is just a rough rule of thumb- every engine combo is different).
Why is the idle so high? You usually can idle lower than that, even w/a stout cam.
Besides the mechanical coming in at idle speed (if that's the case), I'm wondering if this might be a case of not enough initial timing and the carb is trying to idle on the transfer circuit...
More on timing here
. The page was originally on the GM HEI but the timing info still applies. The main difference between the GM HEI and the MSD distributor is the MSD distributor uses bushings to limit the mechanical advance. In some cases, the 18 degree bushing is not enough. If you need more initial and less mechanical timing- like is often the case w/big cammed engines- you need aftermarket bushings