Initial timing and total timing, whats the difference. I mean i think i know the difference is between idle and the upper RPM ( correct me if i am wrong) but how do you set them? I only know how to turn the distributer. Which one is that. Initial i think, so if thats true how do you set total timing?

Initial timing is where the distributor is at. It is checked after removing the vacuum advance line, and should be somewhere around 8 - 12 degrees BTDC. Total timing takes into account mechanical (or centrifugal) advance. A vacuum advance retards timing when vacuum drops, preventing detonation at high load/low engine speed.

So, total timing = initial timing + mechanical advance. The problem is it is impossible to check total timing without some kind of special equipment, since most stock timing tabs only read to 14 or so degrees before TDC.

Advance timing lights are one way to overcome this, as they can be "dialed back" a specified amount so the light can flash at or near the 0 degree timing mark when indicating the specified advance.

Another way to check total advance is by "degreeing" the harmonic balancer, providing additional marks in the vicinity of your desired setting.

So how do you set total timing?

The mechanical advance curve in the distributor uses pivoting wieghts held back by springs to rotate the point cam or reluctor wheel, as well as the rotor. As the rpm increases, centrifical force throws the wieghts out against the spring pressure, rotating the tirgger and advancing the timing. If you take the cap and rotor off, you can see this stuff and turn it by hand to watch it work.

The size of the springs determines "at what rpm" full advance is reached.

The amount of advance (total timing) is harder. Many performance distributors, such as MSD, provide an easy means, with replaceable bushings of different sizes to limit how much the wieghts can use.

With stock type of distributors, the advance amount can be changed with different shaped wieghts, & a different shaped cam that the weights push on. The cams in performance advance kits can often be installed "rightside up" or "upside down" to provide different amounts of advance. Back in the old days, we'd weld or braze up the limiter slot in a stock points ignition, then file it to get exactly the amount of advance we need.

I see. So that bag of parts that i got with my distributer might be important someday :)

Thanks

With the weight and springs under the rotor at a high rpm usually at 3000 you would like all the advance in at that point.

Initial timing is where the distributor is at. It is checked after removing the vacuum advance line, and should be somewhere around 8 - 12 degrees BTDC. Total timing takes into account mechanical (or centrifugal) advance. A vacuum advance retards timing when vacuum drops, preventing detonation at high load/low engine speed.

So, total timing = initial timing + mechanical advance. The problem is it is impossible to check total timing without some kind of special equipment, since most stock timing tabs only read to 14 or so degrees before TDC.

Advance timing lights are one way to overcome this, as they can be "dialed back" a specified amount so the light can flash at or near the 0 degree timing mark when indicating the specified advance.

Another way to check total advance is by "degreeing" the harmonic balancer, providing additional marks in the vicinity of your desired setting.

I thought the vacuum advance was for mileage during high vacuum cruising?? Why would you call it an advance if it retarded?? I must chime in sorry.

If your balancer has enough graduations to see up to 30-40 degrees BTC then setting your timing is easy with the standard timming light. If not you will need the advancing timing light. Or you could do it the old fashion way. It takes two people one one the brakes hard..gassing the motor under load with the brakes on, advance the timing till it just starts to ping and back it off until it doesn't(a very scientific way). Just kidding, we used to do that! Get the timing light!

If your balancer has enough graduations to see up to 30-40 degrees BTC then setting your timing is easy with the standard timming light. If not you will need the advancing timing light. Or you could do it the old fashion way. It takes two people one one the brakes hard..gassing the motor under load with the brakes on, advance the timing till it just starts to ping and back it off until it doesn't(a very scientific way). Just kidding, we used to do that! Get the timing light!

Um, if i do that the tires would go nuts. I do have timing marks up to like 40 though. But i dont think i will be messing with the inside of my distributer. I have the initial timing set close to right if not right so i will just leave it at that untill i can afford to let a professional tune it up for me.

Then take the vacuum advance hose off and plug it. Rev the motor in neutral to 3000-3500 and note the advance. Should be around 32-34 degrees BTDC. (total) The ping method only worked on automatic cars ;-)

Tom, here is a good read about timing. http://www.460ford.com/viewtopic.php?t=21911&highlight=&sid=7dc14d08f98723a0636d73f6ff09a8ce

Stock balancer in use, Mr. Gasket makes timing type, with marks above 40 deg and shows 180 ,just make sure your balancer is real clean ,before applying the type,used years ago before I had to run SFI Fluidamper...Happy Motoring

Tom, setting the total timing is a very simple job. I use a tool called a Jesus Ch***t clip tool. I am sure it has another name, but most people call it that because when the clip goes flying they say "Jesus Ch***t". It's used to remove those really small hair pin style clips on throttle linkage. Here is a link to the tool.
http://buy1.snapon.com/catalog/item.asp?search=true&item_ID=11211&PartNo=ga467&group_id=1445&supersede=&store=snapon-store&tool=all

This makes removing those springs a snap. The instructions that came with your dizzy should tell you the rpm listing for each color of spring. For example, blue spring allows advance in by 3000rpm, green spring allows advance in by 2500rpm, etc. It is very simple. Just use a tool like I linked to and you will be fine. We are here if you need help. If you choose to use pliers instead of the tool I listed, please be careful not to bend the spring. Give it a shot. You may just impress yourself with your unknown ability.