Fiat Dino Forum (FDF)

I have some questions re the Dinoplex ignition.
When my original Dinoplex AEC 101 A suddely stopped working some years ago, I found out Superformance sold new AEC 103 with suitible coil. When ordering
this set, I asked if it really was an original Marelli AEC 103. The answer was: Yes, yes, it´s all original. I soon spotted something else was inside, but I have
used this box until now, without any obvious problems.
But now, having read the forum´s own Dinoplex expert Adrian´s comment that this is equivalent to a standard coil + points system, when looking at the spark
output, I have obtained an used original AEC 103 plus a matching coil. After having hooked it up in the Spider and taken it out for a test drive, I directly have
noticed some changes;
It runs so much smoother in the lower rpm:s range. All signs of hesitation or flat spots are now more or less gone!! After a 30 Km;s ride, I stopped and checked
if the Dinoplex or ignition coil were heated up. The Dinoplex box was somewhat heated, but you could still have your hand on it. The coil wasn´t warmed up
at all!
This ignition coil is marked BES 200 A 12V 6D , not BAE 200A/201A/203A, as stated at Dinoplex.org.
-Adrian, could this coil cause a problem? If so, I have understood I can use the MSD Blaster 2/8200 as a replacement for the Marelli BAE 200A/201A/203A.
Should I use a resistor in series with the MSD coil, or not?
Before buying the Superformance "AEC 103", I tried rebuilding my own AEC 101 A with help of Adrian´s excellent description of switching the original internals
for Bosch 0227 100 137 and coil 0221 122 334. As I like the idea of keeping the distributor points, I followed the wiring diagram and built myself a "impulse
inverter" as described at Dinoplex.org.
At the first test drive, I got 6 Km:s from home, when it broke down. Stone dead, period. Long story short, I never found out what was wrong, so I bought the
Superformance "AEC 103" instead.
-Adrian, I have noticed you dont show the "impulse inverter" in the AEC 101/Bosch conversion diagram any more. Did it cause problems? Is it therefore my
Bosch conversion crashed, or am I just an idiot when it comes to car electronics?

Dinoswede

Hi Dinoswede,

the Marelli BES 200 A is a classic inductive coil for a points and coil setup. It might not handle the high primary voltage sent from the AEC103 on the long run. You can still use it and it most probably won't suddenly fail but if the insulation gets damaged then the spark output gradually deteriorates.

You don't need to run a resistor in line with the coil. As a rule of thumb resistors are only required in points and coil setups, if the ignition coil has a primary resistance lower than 3.0Ω.

I don't have the points/impulse inverter setup listed on my website anymore as the prolonged dwell by using the points setup heats up the coil considerably in lower RPMs, which can shorten the coil's service life. Your setup probably only has a broken wire in the signal path, as a simple test wire up a 12V bulb instead of the coil and shorten the points wire to ground several times, each time the bulb should blink.

Good luck,
Adrian

MANY thanks for your kind and informative answer. I will switch the coil to a MSD 8200, as this is an easy fix. When I get some spare time, I will
take up the AEC 101 Bosch conversion again, following your excellent instructions of how to get it working!

Dinoswede

Adrian, If i understood you correctly the bosch ignition module has dwell and current control, is the reason for using or not using the points/impulse invertor that it will eliminate the possibility of having the dwell and current control?
And how does this dwell/current control work in combination with the luminition OS50? Because at their website i read that the dwell is depending on the 'gap' of the chopperwheel and is always 45deg for a 6 cilinder with there chopperwheels.
Or does this bosch module just need an trigger undependent of how long or short it is and is that why you prefer the bosch module over the luminition module?

With an optical pickup the pulse time is very short so it is not interfering with the dwell time of the Bosch setup (which is quite fast due to the high performance coil, about double as fast as a classic ignition coil).

When using a points setup to trigger the Bosch setup via an inverter, the trigger time (because of the inverted signal) is way too long, so it extends the pulse which overheats the coil as the Bosch module keeps the charge below the saturation until the trigger pulse comes in. See below, the flat top on the ramp (red line) should be as small as possible to avoid heating up the coil.
As the setup with the optical pickup also avoids scatter at high speeds and variations of the advance based on the wear of the cams (and mechanical wear in general), i've choosen the OS50 in the Bosch setup as best trigger setup.

The Lumenition ignition which uses the OS50 optical pickup as trigger works differently, here the dwell is implemented by the width of the chopper blades. The Bosch ignition module controls dwell based on the engine speed and coil charge.