Product Overview
Tegiwa Thermal Inlet Gasket T-1535003 – Mitsubishi Lancer Evo 4-9 4G63 1996-2008
The 4G63 is a famously strong engine, but like any turbocharged four-cylinder it puts a lot of heat into the cylinder head, and the aluminium inlet manifold bolted directly to it soaks that heat up. A hot manifold warms the charge air on its way into the ports, which costs density and makes the engine more prone to knock. This Tegiwa thermal gasket replaces the standard inlet manifold gasket with a PTFE barrier that breaks the direct metal-to-metal path between head and manifold.
What it does
- Fits between the cylinder head and inlet manifold on the 4G63
- Made from PTFE, a material with very low thermal conductivity
- Precision water-jet cut in the UK for accurate port and bolt-hole alignment
- Reduces heat soak into the manifold, helping keep intake air temperatures down
- Works with the OEM manifold and aftermarket manifolds that use the factory flange, such as Skunk2
The benefit is most noticeable in traffic, on hot days and on track between sessions, when heat soak normally builds up fastest. Cooler intake air means a denser charge and more consistent ignition timing, so it pairs well with other cooling and intake upgrades.
Fitment
Tegiwa lists this gasket for all 4G63 engines from 1996 to 2008, which covers the Lancer Evolution 4, 5, 6, 7, 8 and 9. It is not suitable for the Evo X, which uses the 4B11T engine. Full details are on the Tegiwa thermal inlet gasket product page.
Fitting advice
The inlet manifold has to come off, so this is best done alongside other intake or head work. Clean both mating faces thoroughly and make sure no old gasket material is left behind, check the faces are flat, then fit the new gasket dry unless the manifold maker says otherwise. Tighten the manifold fasteners evenly in stages to the factory specification, working from the centre outwards, and check for vacuum or boost leaks once the engine is running.
