I ended up getting a brand new Bosch ignition coil from German Autoparts for around $160 shipped with a few other small parts. This was around November last year.
Go Bosch, or Go Badly.
Performance gains from only a coil, I don't know, probably none, however the car I have it in is completely stock in the engine department. As an addition to mods I think the coil is a good idea because it helps to smooth out these cases when mixture is out of stoich Maybe better throttle response.
0,5l/100km less fuel consumption, consistent, and what is most important, my Golf was the only car that started by itself this winter at -30 C outside, among about 30 cars in our courtyard.
I highly recommend this one: It gives probably the hottest spark out there, is a direct replacement to oem coil and is not expensive (~$30).
It's Bosch KS with a turbo 5K coil. The turbo coil is known to work very well for 18+ PSI, and I am firing it earlier in the cycle than most, which should make the job of sparking easier.
Get the Bosch Blue coil either way though.....
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