I plan on upgrading to the NGK's. They add ~25 horsepower - 15-17 HP to the wheels. They run about forty dollars for six spark plugs.
No, I am kidding. :cover: Depending on how many miles on your car, you probably don't need to switch 'em. But, if you've got around 50,000 miles I'd recommend to get new spark plugs. You won't see any performance gains but you will have better accelerating, gas mileage... cuz the plugs are firing better. They are around $40
The MAIN reason I am upgrading plugs is because I want to run a 75 HP shot of nitrous and to do that you need to have plugs that fire 2 degrees colder than stock AND have a shorter gap. Right now I am just running a 55 shot and I want 20 more ponies :banana:
Hopefully I will have the GMK CAI extension by then so I can put that on, get the new plugs in, swap the nitrous jets and then I will be running 75 extra HP + whatever the GMK CAI extension gives me (~5-8 whp???) Anyways, it'll be a good day!:thumbsup: