For someone who can answer. A one step colder plugs on a car that has bolt ons. Would this affect gas mileage for the better or for the worse.
2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time
i know when you go a step colder for your plugs you can input more timing. the thing is, unless you have HPT, you wont be able to increase the timing. go down a step will help you though if your car is expirienceing detination. when the car dets, the knock sensor removes timing out from the engine. the less chance you have in knocking, the less chance that the knock sensor will activate.
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Injection is nice but id rather be BLOWN!