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