yea, i think it is the car sometimes, i have had many friends put them on their stangs, and its not much of a difference. I put one on my dd corsica, got it on ebay for 40 dollars, so i figured it would be funny to get. didnt make a difference at all. But we put one on my dads 2004 sierra and it made a huge difference. couldnt do a burnout or spin the tires, afterwards if you stomped on it you could spin the tires easily down the street.