Me and my friend just changed the plugs and filter on his GTP. He was running stock NGK'* at 96,000 km it looked like, anyways so we changed them to G-Groove NGK TR55'*, one heat range colder ( his car is stock ). We also got rid of the stock airbox setup and used stock hose and put on a k&n conical filter. It whines now like a b*tch with even the stock pulley but, it seems almost as he lost power. Is it possible that the one heat range colder plugs made that big of a difference? I mean, wouldnt changing the old plugs alone outweigh the fact of the heat range change? Or do you think its the open filter problem? Whatever it is, im just interested. All the spark plugs we tightened hand tight, then 1/4 of a turn. I dont know, maybe im just feeling things wrong. It just feels slower.....

do GTPs need the laminar airflow like we do? also do they have the accordion tube? cause i would think that just puttin a cone filter on the accordian tube wouldnt make for good airflow. just a thought

Hotter air coming in? Just a cone won't draw from behind the headlight anymore.

Yeah you're just sucking in more, yet hotter air. Why the colder plugs? They don't make it have more power, they just help with massive KR.

Don't mean to insult your intelligence but did you insure the plugs were gapped right?

We gapped them at .050. as the old ones electrodes were bent

I thought all 3800'* were .060? I know mine are....

Multiple problems here. Plugs should be gapped to .060, and if done correctly, the TR55'* should be fine.

You're pulling hotter air with an exposed cone. Doing the cone with no supporting mods really REQUIRES a heat shield to be effective. With other mods, the hot air is less noticeable.

Pulling that hot air in may cause more KR, too.

Would the MAF screen make a big difference in airflow also? Like my MAF screen has very veyr very small honeycombs on it, as if it is another primary filter.

I know that most of you have taken yours out but seeing as other sources say that it may cause "rough idling" i'm not sure if I should remove mine.

Only remove it if you want to, and you have a smooth metal pipe.