JBA Cat4ward Headers fits: 2007-2008 Toyota Tundra. JBA Cat4ward Headers Features - JBA Headers replace restrictive stock manifolds with precision built exhaust headers that maximize exhaust flow for major increases in horsepower, torque and throttle response. Increase your engine's exhaust output, which results in an overall improvement in power, efficiency and fuel economy. Dyno testing shows typical performance gains on modern, fuel injected V8s to be 10-25hp with similar increases in torque. Add another 7-10hp with the JBA Performance Exhaust. All JBA Headers are 50 state smog legal and carry a CARB E.O. number (California Air Resources Board Executive Order) that guarantees your modification. JBA Headers. JBA Headers .