Tried to adjust the ignition, but it got me confused.
With the timing light i got the leading set to the yellow mark on the pulley. But when i check the trailing, it is not on the orange mark, but on the other side of the yellow mark. So the trailing is firing before leading.

Its a 12a engine in my car, with a custom wiring harnas on the engine. I must have done something wrong, but i can't spot it. This is how i made it:
The ignitor pointing to the front is the leading and is connected to the leading coil. The leading coil is connected to the L of the distributor. And L1 and L2 are connected to the lower sparkplugs.
The ignitor pointing to the alternator is the trailing and is connected to the trailing coil. The trailing coil is connected to the T of the distributor. And T1 and T2 are connected to the upper sparkplugs.
When i turn the pulley clockwise, the yellow mark comes first and the orange mark second.

What did i wrong?

 

It's a custom wiring harnas that i made myself. I used different colours wire to indentifie L and T. So i got a grey wire from the leading ignitor to the leading coil. And a yellow wire from the trailing ignitor to the trailing coil.

Can it be that a european distributor is different to an american?

 

High tension wires perhaps in the wrong place? Or maybe your timing light is picking up the wrong signal. I've seen what I thought was crossfire when all it was was a cheap inductive pickup getting the wrong signal from an adjacent wire.