ngk pfr6 or pfr7 and gap size
 

i've been searching for about 45mins for a definitive answer and just getting more confused.

last time i got the pfr7b and didnt change the gap , it seemed to be fine .

ive just put the car back on the road after a couple years,it hesitates accelarating around 4000rpm and 5 boost. doing a service should i go for 7s or 6s and what gap,

car is a version 6 sti , so jdm. decat kn panel filter , rest is standard , no ecutek map, i know i should ...

7s and 0.8 gap from memory I think

I thought they were pre-gapped too. My mechanic just fitted my 7's straight from the box. The car runs fine.

They are usually but its good to check.SJ.

I just check if they all look the same lol

would defo use 7's and you can gap them to 0.65mm if needs be.......

thanks for the replies

what do you mean "if needs be " why and when might that be needed , what gap size should i start with

as he said, use 0.65 "blade" job done,if needs be he means if arent pre gapped, just changed mine 3 weeks ago and were with incorrect correct gap.

no the pre-gapped std plugs should be fine but certain modified or high boost cars require the smaller gap of 0.65mm

thanks again for your advise , just to clarify , almost standard version 6 sti , use pfr7b spark plug with a gap of 0.8 straight out the box .

modified cars may need a smaller gap