Ive got about 500 dollars to play with on my truck...Im debating where to spend it.

Initially I was looking at a set of train horns, for the fun factor, and the tank/compressor which will be used later on down the road.

Im wondering what I can get peroformance wise for around that price. The truck has an exhaust and tune right now, and will be undergoing an LQ4 swap, or forced induction in January...but Im looking for something in the mean time.