Originally Posted by
roadracer43
im still researching the grp engines and will most likely go with the grp .21 non tuned engine because it will be my first engine. I do have some concern though with the difference in price with the grp standard plugs. why so much higher than others ? they are $14.49 at amain.
McCoy MC-9 plugs have been very good to me over may years. My grp likes them too.