always best to stick with original equipment modern cars are designed to run what the manufacture uses, i used to work for vauxhall main dealer and the amount of problems you can get from running the incorect plugs is suprising
Avoid irridium plugs on chipped cars, the pointy electrodes can cause hot spots and pinking under load.
Try stock NGK platinums, or for big bost go one stage cooler, ie 7s not 6's.
OR, save yourself a fortune, forget the platimums and go for NGK BKR7E's, one stage cooler, COPPER electrode and cost £1.99 each! Great for bigger boost BUT you have to change them every 5-10k miles.
I got told to go oem spark plugs with a higher heat rating (as i melted one of the tips on my prefacelift!!) Only problem with higher heat rating is that they can carbon up if driven slow.... answer = keep it at the redline!!!! lol
I cannot understand the rationale of buying plugs that are supposed ok for 40k miles....!>!> That is like three years use for most people.
I honestly believe the longlife serviceing idea on VAG cars is ridiculous, it kids people into thinking that their cars will be trouble free for this time period. With a turbo car, if you do regular basic maintenance like oil changes (with decent but not overpriced) oil, every 5-10k miles, plugs once a year and keep you eye on levels etc, they should be pretty relaible. But the longlife idea of oil for 20k miles (maybe 2 years!!), plugs for 40k miles, I think makes some owners forget that they should keep their eye on their cars regualrly.
Although maybe I ma just an old fuddy duddy who remebers the days of mineral oils, turbo times and keeping your points gap correct so your timing is right!!! LOL
I just oredered some Copper NGK BKR7E plugs for my BT s3, its done 8k miles on the current ones since last June. £13.27 deleivered for all 4!. I am sure they will run another 10k miles, but I will feel happier with them changed!!
Well, after looking into it here at Denso, ive found that the IK20s are more suitable for the 1.8T A3 and the IK22s for the S3. Not sure how i came to that conclusion now, lost track of calculations but trust me, RRP is like £5-7 for these plugs and they are Denso Irridium High Power plugs (ideal for modified motors)
the gap should be between 00.28 to 00.32 i went with 00.30 and seems to run fine, the number in the plug name is your heat rateing so 7 not sure what the number equates to really but the higher the number with ngk plugs the cooler they run, i belive some other manufatures heat rateings work in the opersite way around