Saturn S series Twin Cam cylinder head had now featured a new roller-rocker setup with hydraulic tappets and roller cams replacing the conventional bucket lifter setup of the previous engine in the S series. Also introduced for the 1999 model year S-series vehicles that were sold in California was a different type of an exhaust manifold that housed an upstream catalytic converter (this converter had heated up much faster than the conventional unit, and it had also decreased exhaust emissions faster as well), and it also had provisions for an air-injection reaction system (This had injected fresh air into the exhaust to reduce
Exhaust heat management Exhaust heat management Exhaust heat management is the means of lessening the damaging or performance-robbing effects of internal combustion engine exhaust heat by preventing heat from escaping from the exhaust system and into the engine compartment on automobiles. The fact that exhausts often pass near important components means that ways of protecting these components from heat soak are especially important. As a result, heat management is used as a way of reflecting, dissipating or simply absorbing the heat. Heat shield is also useful to reduce under-bonnet temperatures which therefore reduces intake temperature, subsequently increasing power. There are many different types