For those of you running br7es', what is the average life span in miles? I did search, but couldn't find an answer.

 

3-4000 miles

 

There is no average. It depends on your car and what you do with it. However, I would recommend always having at least one spare set and thinking about changing them every 5k or so. I change mine whenever they foul (sputtering under full load) or when I have a big race where I don't want to take a chance. Even so, I always have packs of them spare. In fact, I just bought two boxes of BR8ESs tonight.

 

Thanks Warr. I've had mine in for about 8 - 10K miles, and my car "sputtered" for the first time while doing a hard pull in third this afternoon. I'm Stage 4 (mostly BR's stuff) + FP's Whitte Rabbit. Thanks for the helpful information, looks like I'll have to get some tomorrow. Luckily, NGK's are cheap

 

I change mine every other oil change, which is every 5k miles. On the BR8s after 2-3 weeks I get some funny cold idle behavior, but otherwise they seem to last nearly as long. I may have been changing those every oil change... I only run them now during the race season, when I'm using the nitrous. Hopefully the swap to the DSM ignition will keep the plugs in better shape too.

 

Im good for a change every 3 to 4k as well, all depends on the tune!

 

I change my plugs every time I change my oil.

 

Same here. Yesterday, 2nd gear started to sputter when boosting, so I went to Advanced Auto and bought all 16 of their NGK BR8ESs.