how to adjust static timing?

[MTribe]

Sorry if this has been covered. Did some searching and couldn't turn anything up.

I'm setting my static timing on a 71 TR6 after an engine rebuild. I'm attempting to follow the procedure in Bentley, but nothing's really happening.

I do have a pertronix installed versus points, so I'm wondering if this makes a difference.

Does anyone have a method of checking static timing with a pertronix ignition? I could just try to fire the engine up, but I'm assuming you need to set static timing first to get close?

Thanks! Sitting here in garage wondering what to try next...

 

[tomshobby]

When I installed my dizzy after a rebuild I put it in and snugged the clamp so I could still move it with some resistance. I hooked up the timing light. Then tried to start the car, moved the dizzy once and tried again. It started and I used the light to set the timing and tighened the clamp. That was 6,000 miles ago and I have not touched it since.
Plenty of power, great mileage, runs cool, sounds nice, don't know what more I could ask for.

 

[TR3driver]

You should be able to check it with the engine not running : Fully connect the Pertronix module, coil, etc.; then connect a test light from the negative side of the coil to ground. With the key on (power to the coil & Pertronix), the test light will come on when the virtual points open.

But I haven't installed mine yet, so this is only theory.

 

[tosoutherncars]

*IMPORTANT* though to note, you cannot leave the key in the ACC position for more than a minute or two with the car turned off, or you will fry your Pertronix (if we're talking about the Fireball system.)

 

[MTribe]

Randall, the trick is that I don't have the battery and wiring harness hooked up yet. Bentley (86.35.15) shows 12V --> test lamp --> neg coil lead (disconnected from coil). They say the lamp will light somewhere BTDC, then go out at 4deg BTDC if timing is correct.

I'm assuming the points open and close the coil lead to ground, correct? My understanding is also that the pertronix is a magent/hall effect sensors, so should act just like points electrically.

When I hook up the test lap, though, and rotate the crank, the test lamp never illuminates.

Does that setup sound like it should produce the same result as bentley?

 

[MTribe]

Ah... just figured it out.

You need to apply power to the pertronix module for it to open and close the circuit. I had assumed this was just mechanical.

So the setup (assuming you don't have the wiring harness completely hooked up) is to apply 12V to the red pertronix lead and test light, apply the 12V ground to engine ground, and apply the negative pertronix lead (disconnected from the coil) to the negative side of the test lamp.

The other problem is that had the distributor drive gear off by a tooth--I had the take the gear out and rotate it by a tooth so that the distributor could be adjusted to light the light at the right point, within the limits of the distributor rotation. I found this out by removing the distributor rotational adjustment bolt, moved the distributor beyond the range allowed when the bolt is installed, and voila.

Then you set the timing wheel to 4deg BTDC (in my case, may differ for other distributors), and clamp down the distributor just as the light goes out.

For other novices like myself, also make sure that the rotor in in the distributor is pointing at the cylinder 1 plug wire when the valves for cylinder six are both in motion (meaning that cylinder 1 is transitioning between compression/ignition strokes, where you want it). Otherwise you have to flip the rotor in the distributor around 180 degrees.

I'll put this in a new post for easier searching...

Thanks!

 

[TR3driver]

At the very least, the Pertronix needs to get 12v on it's red wire, as that is what powers it's electronics.

I don't know if it will work with only the test lamp as a load (in place of the coil) as you have described.

So, try giving the Pertronix 12v and repeat your test.

 

[TR3driver]

*IMPORTANT* though to note, you cannot leave the key in the ACC position for more than a minute or two with the car turned off, or you will fry your Pertronix (if we're talking about the Fireball system.)

FWIW, I'm reasonably certain that only applies if the coil is wired up, and the "points" are closed. It's the main power transistor that overheats and burns out, due to the current through it and the coil. Pertronix is distressingly vague about this ...

 

[dklawson]

You are correct. The issue is that when the coil is in the circuit and the Pertonix is powered, around 4 Amps is flowing continuously through the module and it overheats. In normal running the duty cycle is reduced so overheating is not a problem.

You can indeed static time Pertronix. My method is to have the system hooked up "as normal" and put the test lamp between coil (-) and an earth point. When Pertronix "opens" the light will come on, just like when you are using points. Rather than running back and forth to the ignition switch to limit the "on" time of the Pertronix module... I simply unplug its red wire which is connected to my coil (+) terminal since I do not have a ballasted ignition system.