What if I told you that you can gain 5 horsepower this weekend, for less than $100? Or, what if I told you that you could gain 5 horsepower this weekend, for less than $20?I bet you'd be interested eh?Well, the good news is, I'm going to tell you how to gain 5 horsepower this weekend for $0-15 spent. Sound too good to be true? Well, read on!1) Increase the H2O ratio in your coolant - if it weren't for corrosion and freezing concerns, automotive makers would use pure water. Water cools much be.