The power transistor that Bosch uses in their own ECUs is now available to the hobbyist. This is a mod kit for installing a BIP373 in a Megasquirt or replacing a VB921 with a BIP373.
This kit includes a:
330 ohm resistor (used for MS1/Extra and MS2/Extra mods)
The Bosch BIP373 is a replacement for the now discontinued VB921 coil driver transistor. These are almost a drop-in replacement for the VB921, except that they must be installed with a mica insulator as they have a metal backed case. Other than that, they work with exactly the same circuits as the VB921. Like a VB921, they still provide current limiting to protect the other components of your ignition circuit.
More info: BIP373
Tested with MS1/Extra, MS2 standard code and MS2/Extra.