gurnE
if you have a hotter burning plug you are more likely to expierence detination,the cooler the spark the better obviously not to cold otherwise the car will idle lumpy,i spoke to are technician today and he said it is likely to blow the spark out at 1.1mm as they have never ever been set to that and hes worked on cossies since new,we use a motorcraft agpr12pp8 platinum plug,works absolutly perfect everytime.i agree with you a to small gap will cause problems.

Hi guys thank you