I will have to replace my pulley on the supercharger.

I have 2 doubts:



1) 11% or 15% reduction?

I'm tempted to make the 11% reduction like a stock JCW, but correct me or give me some suggestions.

Consider that I installed the original intercooler of a Mini GP with 2 extra rows.



2) Interference installed pulley or 2 piece pulley with bolts.

In the case of the 2-piece pulley, I am afraid that the pulley could slip out although in my opinion, using the correct tightening torques and threadlocker I think that this should not happen.



On the other hand, the interference installed pulley worries me about how far I have to push it down the shaft so that it is correctly aligned.



Heating it up and then inserting it and immediately cooling it with water wouldn't be a problem for me.



Give me some advice on my doubts 1 and 2.



Thanks in advance and best regards