Distributor advance question

[Lbs]

Again.......not real well schooled on this subject. I'm try to dial in my 340 and it seems the more I read the less I know. Can anybody tell me how to figure out how much total mechanical advance I have in my distributor? I'm not even sure I am asking the right question. What I am trying to do is get my initial timing around 12 and my total at about 36. These numbers I was told are a pretty good place to be for what I am using the car for. As a driver, cruise nights, and such. I don't know if I can get to these numbers. If my distributor has too much advance in it can it still happen? :dunno. Then as I read more info the vacuum advance comes into play and gets added into the total timing...........banginghead. Any advice and input is welcome and please remember I don't have a bunch of background on this so you are dealing with a :dummie.
Thanks in advance............pun intended

[HP_Cuda]

It depends on what distributor you are using.

There are different schools of thought but the one I like is to disable vacuum advance set the initial to 16 and let the mechanical which amazingly is 20 degrees get you to the vaulted 36 degrees total timing.

So there is initial timing, mechanical timing and vacuum which adds up to total timing. Think of the use of vacuum more for crusing on the freeway and eeking out that last few miles in gas mileage.

[TelisSE440]

   There are a lot of articles on the subject, like this...

http://www.cuda-challenger.com/cc/index.php?topic=68985.0

[Lbs]

Ok, I have it set now at 13* initial and 34* total with the vacuum disconnected. Sounds real good so I'm going to take it for a drive and see how it goes. Thanks for the input.

[Chryco Psycho]

It depends on what distributor you are using.

There are different schools of thought but the one I like is to disable vacuum advance set the initial to 16 and let the mechanical which amazingly is 20 degrees get you to the vaulted 36 degrees total timing.

So there is initial timing, mechanical timing and vacuum which adds up to total timing. Think of the use of vacuum more for crusing on the freeway and eeking out that last few miles in gas mileage.

 

[blown motor]

So are you guys saying don't run vacuum advance?

[Racer57]

So are you guys saying don't run vacuum advance?

That's like asking which oil is best. You'll get all kinds of responses. 

There's people here that know an incredible amount about these engines, but keep in mind they are not driving YOUR car under YOUR conditions.

Mine has a stock HP383 with the stock style electronic distributor. I ran it with no vacuum for the last 2 years and recently hooked it up. Can't tell a damn bit of difference other than it "might" have less hesitation when I floor it.

[Chryco Psycho]

I never use Vacuum advance , with the higher initial advance it is very responsive & more consistant

[Fern]

So on a distributor that has vacuum advance, can you just block off the vacuum and it automatically becomes mechanical? Or is that just for the stock ones?

[Chryco Psycho]

Yes , plugging or disconnecting the vacuum hose prevents the vacuum from altering the timing so the timing curve is dependent on mechanical only . you can also insert an allen key into the hose nipple of the vacuum advance a turn the screw approx 14 turns counterclockwise & limit the vacuum advance that way .