What kind of gas do you put it it? You could of gotten a bad tank of gas. Plus this cold weather leans your fuel out as well. So the combo of bad gas and the cold weather meant you could of heard some detonation a little bit.
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"Gripping the wheel his knuckles went white with desire, the wheels of his mustang exploding on the highway like a slug from a .45. True death. 400 horsepower of maximum performance piercing the night, this is Black Sunshine"