International Lancia Forums

i have a question about the wiring to the coil and ballast resistor. on all of my other cars, the battery wire was led to the resistor first then to the primary side of the coil. (resistor in series with the hot wire) the secondary side of the coil was led straight to the distributor.
on my s1 sport 1,3 engine, the resistor is in series on the secondary side of the coil. my manual also shows this to be correct. what is the reason for this? is this really the preferred method? i was all set to re-wire this but thought i would look at the manual first, now i'm not sure...

Are you sure the resistor is connected to the secondary side of the coil? On page 07/9 of my manual reprint, a ballast resistor is shown on the primary side. Specifically, the low tension wire from the ignition switch goes to one primary terminal, then the other primary terminal goes to the ballast resistor. The points go to the other side of the ballast resistor. Sounds to me as if your wiring is correct as it is.

This is different from what you see on many cars, where the ballast resistor goes between the ignition switch and the coil primary. However, it doesn't make any significant difference where you put the resistor, before or after the primary winding.

I'm pretty sure my S2 didn't have a ballast resistor, or at least it was built into the coil. But I've replaced all that anyway with a high energy electronic system - one of the best things I ever did to the car!

Peter

Peter is correct. On the Fulvia the ballast resistor is between the - (minus) terminal and the contact points. The ignition wire is connected to the + (plus) terminal. Note that internally the minus of the high voltage winding is also connected to the + terminal.

A ballast resistor is only necessary if the primary resistance of the coil is less than 3 ohm. Typically a standard coil such as the blue Bosch has a primary resistance of about 3,3 ohm. It does not need a ballast resistor. Some coils have a primary resistance of 1,5 ohm such as the high energy red Bosch coil. If it is used with contact points a resistor of 1,8 ohm has to be put in series to limit the current through the points at low rpm and when the engine has stalled with ignition still on and points closed.

The advantage of having a 1,5 ohm coil with external ballast is that a lot of heat is kept outside the coil.

i have the bosch red top coil on my setup. i will check with my ohm meter to verify the resistance. does having the ballast resistor on the points side of the coil affect the ability to check the dwell setting with the motor running? my trusty old analog dwell meter is having a little trouble here. maybe time for a new meter?

I would expect that having a ballast resistor should not influence the reading on the dwell meter whatever side the resistor is on. You might try the various combinations and see if it makes a difference.

i'll give it a try & see what happens. i recently changed the points to a set of marelli ones that came with the car. it seems to have made quite a difference in performance. just wanted to verify the dwell setting though.
thanks for the help,