I\'ve posted this question on the SXOC forum but haven\'t had any very helpful answers, so perhaps someone on here can help.
I\'ve just changed the spark plugs in my S13 from Splitfire SF 392C\'s to NGK BPCR7ES-11\'s as my boost is at 15+psi.
I am assuming that these are colder plugs to the Splitfire ones, (they are gapped to 0.9mm on advice from SXOC) but the car seems a little less aggressive now, and not so potent.
Do colder plugs burn less itensely and consequently reduce the power a little?:confused:
:rolleyes: bump!:D
you might find with the colder plugs you need an ignition booster, i had a similar problem, HKS twin power fixed it! 11\'s are quite a cool plug, you might want to try 10.5\'s or 10\'s depending on what you had before.
Cheers
I think the temp. indication is given by the no. 7 as the standard manual recommends BPCR6ES-11\'s.
Although it does sound like I\'m not getting such an intense spark from what you\'ve described:)
I might try and close the gap to 0.8mm apparently this is o.k.
sorry, i misread the part number, Rx7 have two 7\'s and two 9s, but most people run 9s standard and 10s or 11s on high boost models. 7s are not actually that cold in this case.