MC tweaks-Distributorless Ignition

[JShadzi at aol.com]

There are sevarl issues with distributor ignition in general.  For one, the timing accuracy of a distributor ignition is poor due to cam belt slop and also rotor phasing to the distributor.  Cam belt slop explains itself.  Rotor phasing is an entirely other issue.  When an ingnition dist. system advances or retard timing, its manifest in the firing time of the rotor to the dist. cap.  When high retard or advance occurs, this usually means that the rotor is at some distance before or after the contact point in the dist. cap for that particular cylinder.  This results in large spark gaps which weaken spark energy at high advance or retard levels.  The highest retard levels occur under max. boost in a turbo car, just when you need the most powerful spark.

The other issue is firing off big HP with one igniiton coil.  Read my notes from one of my last dyno days for more detailed explanation of this at:  http://www.80tq.com/Dyno0903.html
But to fire off a highly boosted combustion chamber, say over 20psi, it takes a reasonable amount of advance and spark energy, both of which suffer in a single coil, ignition dist. system.

Running 034efi IIc on my 80 allowed me to take my boost up over 20psi on 91 oct., where with the IIb system I was limited to about 18psi, and needed 100 oct. inorder to get the advance back to fire off the mixture, the spark is so powerful with IIc that it will fire of crazy boosted mixtures with only 6 or 7 degrees of advance, where with the dist system anythiing less than 12-15d resulted in missing.

Hope this makes sense, feel free to ask for clarification.

Javad

>[..bigger turbo .. cam ..dual pass..Ignition timing..simple things you could do w/o any
>major fabrication..Header..right turbo   <- edited
>:
> "in conjunction, and IME, once you want to get much past 350 crank the
>ignition dist. has got to go. "  Javad]
>
>Why does the (stock?) distributor have to go, please explain?
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