Should dwell change with rpm

[Don]

Using the sun machine ,I notice the dwell decreases a couple degrees with about 2000 rpm,new bushings and points,,is this normal? Weak point springs?

[BUBBAS IGNITION]

Typically 3 degrees of change is ok thru out the rpm range.
Dwell will change as rpm goes up as the time required to build and fire the coil shortens up.
For every degree of dwell change actually timing change is 2 degrees at the balancer or engine timing.
Starting at idle the dwell will change (build up time) untill the build up time is so low it can no longer fire the spark plug. The sun machine will show this point as extra arrows or missing arrows....

[Don]

Sponsored Links (Register now to hide all advertisements)

Thanks for explanation ,that's exactly what I have. Good info