When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
If you drive with the gas cap off, it makes more power because more oxygen is getting into the gas. When the cap is on, the vacuum starves the gas of oxygen. More oxygen = more power.
You should also route a hose from the exhaust pipe to the gas tank so that it pushes the gas into the engine faster. Also, splice in a tube that leads to the cabin, press recirculate and close the windows.