Distibutor advance

[Steelmuscle]

Edelbrock recomends the initial on my cam to be set at about 12 degrees. Mopar recomends no more than 35 degrees total advance. I have 30 degrees mechanical in my distributor now. I would need about 20-24 mechanical + my initial to arrive at the magic 35 degrees. Does anyone know of a simple way to change the mechanical? I noticed in another post that MP may offer a new unit with adjustable advance. But is there a cheaper way?

[mtrv8n]

Your total advance is what you should worry about first. Try it at 35 - 36 degrees, and if it starts easy and does'nt knock, don't worry about setting initial.
On the other hand, if you really want it dialed in, you'll need to supply Don with all your engine specs and a few bucks to modify your distibutor.

[Bigfoot]

Two easier/cheaper ways.
1. Go to the junk yard and find a 70's-early 80's vehicle with the same type of engine as yours SB or RB/BB and look for an emissions sticker that has an initial setting of 14 deg btdc and remove the distributor. What you want is the advance plate that limits the weights. There should be a number stamped on the plate and X it by two to get the amount of mechanical advance in the plate. i.e. 15 means 30 deg of mechanical advance, 11 means 22 deg.

2. Take the advance plate out of your distributor and weld the slots up about 3/16" or about 1/4 of the way that they are now. With calipers measure each side and make them the same by dremel tool or a small round file. Put everything back together and install it in your car and see how much mechanical advance you now have with a dial back timing light. If you need more advance than you now have to remove some more welding on both ends and keep them the same, if by chance you need less advance you need to weld some more on. Keep doing this until you have what you want.

As far as the advance curve goes you will also have to experiment with different spring sizes, the smaller the springs the faster the curve will be. A good 2-3 hours and you will have it close. For a perfect curve and mechanical advance you can also send it Don (cuda66273) and he rebuilds the complete distributor to your exact car/engine combo, you won't be disappointed.