free or cheap horsepower

Hello everyone- i have a ford ranger 2.3 manual (this is the same exact motor and trans and the mustang 2.3)> Are there any free or cheap way to add horsepower?? Anything will be appreciated:smoka:

Bump the timing a few degrees untill you get pinging, then back it off a bit. Maybe a K&N air filter. My first car was an 89 mustang with the 2.3, there really is not alot you can do to them.

thanx