Ok, initial + vacuum + centrifugal advance = total advance timing.

What should the highest total be?

This figure does not stay constant does it?

As long as detonation does not occur, you are within safe timing limits. True or false?

Can there be detonation that you can't hear?

Thank you.

 

That would be the total on cruise/part throttle driving.

But generally when timing is spoken of in terms of "xx*'s, all in by xxxxRPMs", you're only looking at what the distributor's mechanical advance is capable of.

At WOT, there is no vacuum advance, the only advance the ignition is giving is from the centrifugal action of the distributor throwing the weights out.

I'd guess that maybe about 45*'s is the most you'd see.

 

What ever you can get away with that will not cause the detonation and will not cause NOX emission to go through the roof



Nope

Yep, depends on what type of exhaust you have and how good your ear is.


It rarely happens at steady speeds. Listen at very light acceleration and full throttle mostly. Each is a reflection of a different thing going on inside the motor (and can be addressed by changing the relationship between motor and research octane, if you have the ability to make such a change).