I do not have A P91 laying around, I run 2 150s in a C3 w/P90 also in a L6 body with a KT2 head and MN16 bulb
not sure what bulb is in my Z3 with Turbo head but its running on Pila's 2 150s with the KT turbo head on the L6 I used the Pila spring that Jon has did not need one with standard heads. I hope that helps.
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