Can I safely assume that if you advance or retard your timing by X degrees at idle RPM, then that exact same advance or retard value will be seen and measured at 3500 RPM? In other words, is there a linear equivalent going on, or is there a more complex relationship going on, whereby a different change will be measured at the higher RPM? Hope I was clear on this.

Ansbacher

yes after the counter weights within the body of the distributor fully wind out at 3500 rpm... then yes... the one or x number of degrees you advance or retard should be the same.


don't adjust it at Idle
its meant to be adjusted at full advance (3500 rpm or higher)
and disconnect the vacuum line to the distributor

With regards to statics or any static measurement you are taking a point on a line
to another point.


So if the question regards static timing yes....you are measuring a point at idle and then one at @ 3,500 rpms and since and if the weight's on the dizzy max out advancing the spark in relationship to the crank then you are simply translating the initial static advance.


So dynamics are measuring what the timing should be at 2,000 rpm's cruising down the highway at what HG. So based on the engine needs ......and probably not linear from the statically measured two points.

Of course....the specs are for the stock engine design and if the induction or camshaft is changed so will the engine needs and any point.

So the answer is.....yes??....(a bit too technical for me). The reason I asked this question originally is to cover the following situation:

Let's say I know my car is set at 29 degrees at 3500 RPM and I want to bump it up to 30 degrees. It is an early Sunday morning and I don't want to bother the neighbors by revving the engine to 3500 RPM to make the adjustment. Therefore, can I just bump up the timing at idle by one degree to achieve 30 degrees at full throttle?

Ansbacher

Sorry...simply yes. However like Brant says...make sure you disconnect the vacuum advance or retard side and plug the TB side if a stock dizzy.

This won't account for dynamics when the engine is on however....which was what thought you also wanted to know.

Personally I'd not worry about what the neighbors think in that I'd want to know what the engine is doing throughout the rpm range with everything running and working.

I also wonder if a cold motor verses a warmed up motor would additionally contribute to a degree difference?

I wouldn’t trust it
Just rev it is my vote
Better to test it per spec for repeatability

Brant

cold motor/hot motor should make no difference as the mechanical advance relys on centrifugal force.