Installing a S/C pulley upgade 15% from mini madness. They recomend a cooler plug. I checked two local stores and they show stock as a 6 heat range and the only plug with a lower range is Autolight? Any thoughts on this as to brand and heat range. I track the car several times and run hard for two or three days so engine detonation would not be fun.

Thanks to all, as always, great group

2005 Mini S