Im just amazed what new spark plugs can do for your car! Its been about 30k plus miles since ive put in new plugs in my 8. I just recently had a new motor put in my mazda and decided to change the plugs at 8k on the new motor. I was starting to get a real rough idle and seemed a little boggy, also getting a missfire code every now and then. So I take my car for a quick test drive w/ the old plugs in and then proceed to put my new plugs in. Its crazy! How much difference there is! The car pulls soo much harder and now again will lay it sideways at w.o.t in 1st and can keep it while shifting into second. I thought my car was running pretty good, its crazy how over miles of driving losing a few hp here and there you dont really think of it much till you put your new plugs in and its the best hp mod you can do! I just wanted to rant about that for now, im just pleased how much better my 8 runs now. it feels like im runing nitrous w/ out nitrous, cant wait to fill my bottle and see what she does!

 

i gotta do mine soon too

 

hell Id change the plugs every 15k if it wasnt a 100 dollar bill for 4! Get on it you'll fall in love w/ your 8 all over again!

 

i got my plugs at autozone and they have some ridiculous warranty on them, so i just keep taking them back and getting new ones for free.

that original $84 i spent has netted me 3 sets of plugs.

seriously. check out the warranty information.

 

WOW! i gotta try that!

 

I was amazed too when I first changed mine. Back to a smooth buttery ride.

 

When I bought plugs about six months ago for my '04, the dealer was the only place that even listed them. What brand / part number does Autozone have them under?
By the way, if they don't last very long it's probably the wrong heat range or something. Bosch use to do a good job of researching the correct plug for the US driving style. But, so far, Bosh dosen't have a listing for the RX-8, unless it's recient.
I'm still due free hotter lead plugs on the recall. Hate to let the dealer mess with my RX-8 !!! He won't just give me the plugs and call it even.

 

No its the car.