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Quickstep192 Quickstep192 is offline
'73 911 T Targa
 
Join Date: Dec 2009
Posts: 1,359
Garage
Quote:
Originally Posted by Nux View Post
Yup thats correct. The dizzy advances the ignition timing by a complex system of springs and weights. But this way, the timing curve is always the same. Example: You want WOT timing to be further advanced than the stock 24-26 BTDC. You would have to advance the timing at idle as well (or have the dizzy re-curved).

There are 3 ways to use the CDI+:

1. Plug and play - dizzy is still in control. What ever benefit (if any) is from the "double" ignition and much more powerfull spark.

2. Set the dizzy too advanced and let the CDI+ electronically retard the timing. This is what I do at the moment. If the CDI+ didn't retard timing, I would be running 10-15 BTDC at idle - and the car would not idle or start very well.

3. Lock the dizzy out at fully advanced and let the CDI+ completely control the timing. My next step - and go to a dyno to set the optimal timing.

Thanks for this great explanation. Cool stuff...
Old 07-13-2017, 01:01 PM
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