unless your doing something crazy, like putting some boost in the motor, and spending excesive amounts of time in high revs there isn't much of a benefit or need from what I remember researching.


87 Toyota 4Runner-RV Head, Custom Grind Cam, Doug Thorley Header, Keith Black Pistions, 2 1/4" Magnaflow cat, Dynomax Exhaust
2003 Toyota Matrix XRS-Injen CAI