transistorized ignition systems

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Hovis
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transistorized ignition systems

Post by Hovis »

Hi does anyone know what the transistorized ignition system unit do? andwould there be any difference between the carb and injection ones?
cheers


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Funky Diver
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Re: transistorized ignition systems

Post by Funky Diver »

It tells the coil when to fire the spark on the plugs basically... least that's how I understand it.


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fonzooorooo
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Re: transistorized ignition systems

Post by fonzooorooo »

As I understand it, the distributor decides the time the spark is sent...
If you didn't have the electronic module, you'd need "points" in your distributor (effectively a switch which carries the high voltage [coil trigger - not HT], which wears/burns out/needs re-setting/copious maintenence) That's the system that pre-dates transistors. With transistorised ignition, I presume such a switch must still exist, but carries a low (electronic level) current/voltage. This is then amplified by the module to a level sufficient to trigger the coil.
Modern stuff's replaced all that with crank position sensors, engine control units and coil packs.


Hovis
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Re: transistorized ignition systems

Post by Hovis »

awsome cheers guys, i guess there wouldnt be a power gain to be had by swapping my gt2 one with a gti one then.


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Funky Diver
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Re: transistorized ignition systems

Post by Funky Diver »

Not in the slightest.

You could replace the whole dizzy setup though ;)

Using something like MegaJolt, it won't give you more power, but it will allow you to fine tune your ignition using MAPS - effectively you decide how your engine runs and idles through adjusting the spark timing (much like the carppy vac advance thing on the dizzy currently)

It would mean you would be ditching...

TCI Module - in the bulkhead
Distributor
Vacuum lines running to dizzy

and replacing it with

Control Unit
EDIS or Coil driver gubbins
Crank sensor with wheel - for timing reference


And to give you an idea of the difference between a standard points based ignition and an electronic replacement

http://www.youtube.com/embed/qSQ7t5I6rcQ
Last edited by Funky Diver on Mon Mar 07, 2011 11:34 pm, edited 1 time in total.


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fonzooorooo
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Re: transistorized ignition systems

Post by fonzooorooo »

Hovis wrote:awsome cheers guys, i guess there wouldnt be a power gain to be had by swapping my gt2 one with a gti one then.
No. There wouldn't.

Unless your engine's already had extensive tuning work, I'd think it'd be reasonable to suggest that as long as the ignition system is in good order/condition, then leave well alone, and concentrate your efforts elsewhere. (fueling, air, head work, cam etc.)


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