Discussion in 'Engine Combos and Dynometer Database' started by Indycars, Nov 3, 2010.
love the posted picture quality
Ideally you want to check the Secondary KV pattern.
Super imposed pattern.
Actual Dwell time per cylinders all 8.
Ignition firing time.
Have my Snap On CRT Counsler Digital Ignition Storage Oscilloscope.
It was about $10,000 new .
Bought it from a Friend that closed down his Auto shop.
Still paid good money to make it mine.
$600 back 2001.
Some checks can be made with a standard CRT oscilloscope.
One mistake though and it will blow up from the High Kv secondary ignition voltage.
There is also coil saturation time too.
We are in an era of disposable everything.
It's remove and replace today.
I am one of the last mechanics to learn all electronic ignition fundementals.
Points & Mags also.
If you found no vacuum leaks at all then install the ebay distributor you have from testing back 1-1/2 years ago.
See if it hits clean on all 8 cylinders again.
My ignition timing is stable now compared to the video I took on Feb 20, 2016. Shown below.
The MSD module has changed, I read on YouTube that someone had the same problem with stability
and I had changed it after the video. So I can't say for sure if that cured the problem or the change below.
This winter I changed from a cheap Professional Products damper PN#: 8002 to a Fluidampr 62260D 6-1/4" OD Gold Harmonic Damper.
Below you can see how the ignition timing has stabilized. At about 7 seconds it will clear up, look for the black dot at 36°.
The 2nd video I can not see your black timing mark.
I use a white paint stick paint pen to mark TDC.
I have a Pontiac Egg Shell Blue paint stick pen that also shows up well with a Xeon flash strobe light.
Did you find a vacuum leak or not Rick ?
I won't have time till this weekend.
Have to make a video again.
Show how my Snap On Counsler Ignition Oscilloscope works.
Connect to my 1987 Corvette.
It also works on my Vertex Magnetos.
Spin test a Chevy & Pontiac V8 Mags in my SUN Distributor machine.
Absolute Best way to test for unusual ignition problems.
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