I was told the stock retainers and springs are titanium, is this true? Also the valves are sodium filled to help decipate heat?

 

springs are not titanium, valves are sodium filled, retainers--I don't know.

 

Retainers are aluminum...

 

Isnt the valve cover magnesium>?

 

yes

 

Lancer Evolution’s engine features numerous weight savings refinements that help improve the vehicle’s performance.


In the interest of refinement and increased performance from the Lancer Evolution engine, Mitsubishi engineers have progressively improved the design with numerous weight saving measures. The Lancer Evolution’s engine is equipped with a super-lightweight cast magnesium rocker arm cover, which, along with hollow camshafts, helps reduce the engine’s top-side weight and reduces it’s center of gravity in the chassis. The reduced mass of the hollow intake and exhaust camshafts, along with more compact, tapered, bee-hive shaped valve springs, featherweight aluminum retainers, and lighter, natrium-filled exhaust valves reduce valvetrain inertia and help improve the engine’s responsiveness. The stainless steel, natrium-filled exhaust valves also help lower the temperature of the bell end of the exhaust valve by retaining less heat. The cylinder head is also equipped with hardened, sintered metal exhaust valve seats that are better able to resist the forces of heat and pressure.


The Lancer Evolution motor utilizes hollow, belt driven camshafts that help reduce valvetrain weight and inertia.


The 2.0-liter engine’s elastomer-filled, vibration-dampening crankshaft pulley is manufactured from aluminum and reduces pulley weight by 340 grams over the standard Lancer engine’s pulley. The engine’s accessories are powered by a single serpentine belt system driven by the crankshaft pulley. In addition, the engine utilizes a more compact balance shaft arrangement to help give a smooth-revving character while reducing the power-robbing inertia of the balance shafts.



The turbocharged 4G63 engine equipped in the Lancer Evolution sedan uses high-flow, natrium-filled exhaust valves to help reduce valvetrain mass and help reduce the amount of heat retained by the exhaust valve’s bell shaped end.


Compared to the Lancer sedan’s springs and retainers, the valve springs used on the Lancer Evolution series are smaller, stronger and with the help of an aluminum retainer, reduce valvetrain mass.


The larger, cast magnesium Dual Overhead Cam cover weighs less than the smaller Single Overhead Cam unit that appears on the base Lancer engine.