SMG/K FA20 T=0.7

Opposed Bead Stopper Type Metal Gasket for the FA20 engine of 86/BRZ provides higher bore sealing durability than a stock gasket.
2 types of the gasket are available. One is t0.5 increased compression ratio type for an NA engine (ε12.6←12.5, Supercharger installable, Endurable approximately 300ps)and another type is t0.7 high engine output type for a supercharged engine (ε12.4←ε12.5, Endurable approximately 600ps with supercharger)

■ Feature

<POINT-1> t=0.7mm for Supercharged Engine

The t=0.7mm type utilizes a stopper taller than the t=0.5mm type to provide higher bore seal durability. With a stock pistons, the compression ratio is reduced only by 0.1; it allows to maintain high heat efficiency.
Compression Ratio
Stock Thickness: t=0.6mm (ε12.5) HKS Thickness: t=0.7mm (ε12.4)

<POINT-2> Maintain a high seal with high pressure!

Both types are endurable against high engine output. Stopper structure of the bore seal is separated type so it prevents leakage even under high gas-pressure at high engine output.

<POINT-3> Contact surface pressure is improved!

Special coating was applied on the head side and cylinder side to improve sealing performance when tightening the bolts.

<POINT-4> Bore seal pressure was confirmed in figures. (See the diagram below.)

(Contact Surface Pressure Measurement)

(Contact Surface Pressure Measurement)

(Structure Comparison)

NA　t=0.5

* Comperd to stcok, bore seal is independent and has higher seal surface pressure,
　therefore same amount of stopper, bore seal is stronger.
* Thinner than stock and compression ratio is 0.1 higher

Supercharger　t=0.7

* Comperd to stcok, bore seal is independent and has higher seal surface pressure,
　therefore bore seal power is much stronger.
* Thicker than stock and compression ratio is 0.1 less than stock

Stock　t=0.5

* Bore stopper is similar to the other seal and ther surface pressure polymerize,
　it has lower seal ability than the independent type