So i am currently upgrading the retainers in my 2000 ap1 to ap2 retainers and since i have access to them i figure i might as well replace the 11 year old spark plugs in the car. As i am doing a lot of autocross and the car is in the process of being converted into a track car i figured i would ask what the R&C forum had to say about various different spark plugs. Also i tried the search and the most recent post it came up with was from 2001.

Thanks
Greg

 

I just replaced my plugs maybe 20K miles ago. I am noticing some brown discoloration around the nut on the ceramic area. I'm probably going to use the BKR8EIX when I switch.

 

I think its the BKR8EIX I ran (colder) and I felt like the car lost power. It might have been because I didn't gap them correctly I think they need regapping.
I went back to NGK IFR7G-11KS no gapping and the car felt much better.

 

Unless you are running forced induction or a lot higher compression a colder plug is going to cost you HP. On our 1000 WHP turbo cars going 1 heat range colder would drop 15 HP with no other changes.