I get that but why would zero resistance wires etc from the dizzy to plug cause upstream issues with the amplifier that (if I am right) amplifies the input signal to help the coil generate higher voltage Th reason for asking is that I am (I think) having lots of issues with amplifiers once the whole system warms up
Hi Andrew, I went down the same route... I originally bought a set of leads from https://simonbbc.com/Ferrari-208-GT4-308-GTB-308-GTS-HT-Leads-8mm-Double-Silicone These were high resistance leads - as you know I tried lots of different ignition modules/coils etc. without success. I then made a set of leads up - buying the parts from https://www.gsparkplug.com/ I spoke to owner of the company and he seemed to know the system, the cable he sent out was low resistance... and as you know, I still haven't resolved the issue. I'm using NGK BP6ES plugs (not resistive) and extenders that have a little over 2k ohms of resistance. I found this snippet in an old thread (there's plenty of them) from Steve Magnusson who knows his stuff. The stock 308 carb setup is: spiral wound spark plug wires (has resistance of ~700 Ohms/foot and some inductance from the spiral winding form) extenders with resistance non-resistor spark plugshttps://www.ferrarichat.com/forum/threads/some-ignition-system-confusion-on-my-newly-acquired-1975-308gt4.560351/ I'm sure this probably adds to the confusion. Happy New Year!
"Amplifier" is not quite the right description (although transistors can be used as amplifiers). An electronic ignition has a high-power transistor to switch the current in the coil primary, but the impedance of the secondary circuit affects the voltage spikes that appear in the primary circuit (i.e., the primary circuit voltage is not just a simple 12V -to- 0V rectangular wave) and these voltage "spikes" in the primary waveform can stress and blow-up the transistor: Image Unavailable, Please Login https://www.slideshare.net/kimmimaru/waveform-ignition You'll want your secondary circuit to have a non-zero impedance -- that's why the stock Digiplex F models use helically-wound spark plug wires (that have a non-zero inductance and a non-zero resistance) and resistive extenders.
