How much mechanical advance from a Mopar electronic?

[Whitehatspecial]

What is the total mechanical advance from a Mopar (la 340) electronic distributor? I sent mine out locally to have the vacuum eliminated and have it "curved". It throws a total of about 15*, checked with a digital light. Seems like it should throw more. 
Sorry if this sounds like a stupid question, but does that mean if I set the total advance at 35* at 2500 rpm's then I will have about 20* initial?
This is an iron head 340 with about 9.5 compression, dual plane intake and BG 650 carb, .227 high energy lift cam at .050".

 

[Jacksboys]

Mine will only move about 10-12 degrees, so I set mine at about 20 initial and about 30 total, but I am a little over protective of my parts, so I do not care to try 35 right now.

If I was you I would set it to 15 initial and 30 total and make sure it will not ping.  If not then raise it to 35 if you want to.  If it does not ping, then you should get slightly better performance with the 35 degrees.  Your choice. 

You can try connecting the vacuum advance, but there is a chance it could ping with the 9.5   compression.  I leave mine unconnected.

[matt63]

Your initial advance is read at idle ie 15 degrees.  This is adjustable by turning the distributor cw or ccw.  The full advance is ready by speeding the engine up to approx. 2500 rpm ie 35 deg (max advance can come in before or after depending on the dist).  The mechanical advance is the difference between the initial advance iand the total advance ie 20 degrees.  Adjustability in the mechanical advance, depending on the distributor, is internal.

[Chryco Psycho]

with a 15* curve & total set at 35* your initial will be at 20* ,
you can actually do more damage by running the engine hot with the timing at 30* total , I would bump it to the 35-38* range as long as it doesn`t ping 

[Jacksboys]

with a 15* curve & total set at 35* your initial will be at 20* ,
you can actually do more damage by running the engine hot with the timing at 30* total , I would bump it to the 35-38* range as long as it doesn`t ping 

 
I am not saying you are wrong, but if that is the case, then how do the modern engines run on less advance and not have over-heating damage?

[Mopar73340]

Both of my 340 factory electronic dist's have around 25* of mechanical timing in them. I have switched to the MP units which have the ability to limit the total amount. I currently run them with 18* inital and 35* total all in by 2500, so you should be good where you are. They run much better with more inital timing than the 5* the factory calls for. They also run much better with the vacuum advance hooked up. Just my