[jessgator1]

Had my '66 for about a month now and just installed Pertronix II and a Flame Thrower Coil. Checked the timing and the timing is sitting at 23 degrees (book says 6, I was planning on adjusting to 8)

Did not check the timing prior to installing the Pertronix because the car ran so well. And, the car is running really well right now as well.

Any chance the timing light is out to lunch?

I called the support fellas at Pertronix and the guy said that he thinks that some how the Pertronix is causing the timing light to miss, or screw up, or something like that (I don't think he convinced himself, either).

The only other thing I can guess is that maybe the balancer is not a stock 289 balancer, but I'm 99.9% sure it's the stock balancer.

I don't like just leaving it "because it seems to be running well" - I want to know what the heck is going on and want to fix it.

So - anyone installed Pertronix II and coil into a 289 and see something similar, or have any ideas what could be causing this?

thanks

 

[Joes72/65]

If the engine has not been rebuilt within memory, the timing mark on the harmonic balancer may be off. As they are mounted in rubber, they move over the years. I cannot see the mark at all with a timing light on my '72, and on my '65 it is so far off that it's only useful to see if the vacuum advance is working. I time both with a vacuum gauge and tachometer.

 

[1966er]

I agree with the vacuum gauge & tach method. I am using the Pertronix II w/Flame thrower coil in my stock 66 289 w/4 barrel.

I adjusted the timing until I reached 18 in of vac at idle & 600 rpm in drive.

 

[jessgator1]

I'm a little confused as far as checking the timing goes. I rubbed chock on the balancer to fill in the indentations and then tested the timing - didn't notice any way that "TDC" and the 3/6/9/12 degree lines could have moved themselves.

Unless - and i'll preface this with "newbie here" - if the motor was rebuilt and the balancer wasn't positioned exactly right with the TDC line lining up with the timing mark on the motor when the #1 cylinder was at TDC - would that cause my timing to always be off?

I.E., if the "TDC" on the balancer when it was installed was - let's call it 17 degrees forward of the timing mark when the #1 cylinder was at TDC - then if I show 23 degrees with the timing light, I'm actually seeing 6 degrees forward of the true TDC? If that's feasible, then is that a possible reason as to why I'm seeing 23 degrees?

I'm still trying to figure out the "science" behind the whole timing thing.

thanks

 

[sixtsixstang]

If that rubber has shifted, you need to replace the balancer. You'll be upset if the thing comes apart on you while driving down the road!

 

[jessgator1]

Ahhh, okay, after staring at the balancer a little more I think I see what you're saying.

Confirm that the entire hunk of rubber on the balancer can shift itself? if so - makes sense.

Think I'll use the vacuum technique

 

[Joes72/65]

Yes, the entire chunk of rubber shifts over years and years of happy motoring!