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Posted by: ChrisReale Apr 10 2003, 12:03 AM

What are some signs that your points need to be adjusted? (Not related to my Pertronix question earlier, just curious)

Posted by: MarkV Apr 10 2003, 01:08 AM

Dwell:

Dwell angle is the time for which the points remain closed before opening again. Which here relates to the gap between the points when they are fully open. The Dwell, at any speed must be MORE than the time (microseconds) needed for the current in the primary of the ignition coil to rise to it's saturation value. Or else the spark energy / power will suffer. At this stage, suffice it to accept that the Dwell is a problem felt in high-revving multis. Of course, the points must be free of bluing, residue, corrosion, erosion, or misalignment. Or else the achieved saturation value of current will be less than that designed, which will lead to a weaker spark. :toilet:

Posted by: airsix Apr 10 2003, 10:49 AM

Like Mark said, gotta check the dwell angle. Using a feeler guage to set the point gap just doesn't cut it.

1) adjust the dwell angle (get a meter - they're cheap) Once you have the meter you can easily check the dwell in 2 minutes whenever you want.
2) adjust the timing because changing the dwell changes the timing but not vice-versa.
3) If your dwell angle and timing bounces around like a ping-pong ball then your distributor is worn and the shaft is wobbling. Converting to electronic ignition may make this better since they are less suceptible to shaft wobble (especially the Crane optical kit).

-Ben M.

Posted by: tryan Apr 10 2003, 11:34 AM

.001 change in point gap can throw off your timming 2-3 degrees.

Posted by: ChrisReale Apr 10 2003, 02:48 PM

What I meant was what are some signs that the car does to tell you that points need to be adjusted? Like, a stutter, misfire...?

Posted by: airsix Apr 10 2003, 03:34 PM

When they need adjusted you won't notice. You'll have to check them to tell.
When they really really need to be adjusted you'll notice less power.
When they really really really really need to be adjusted it will start missing.
When they really(x5) need to be adjusted the engine won't start.

-Ben M.