3rd Drive Gear TY856 6MT Ratio 1.521 REM ISF:Yes (+$40) COBB's boost control solenoid provides

COBB's boost control solenoid provides stable boost levels from everything from stock boost pressures up to extremely high levels associated with big power builds

Replacement rubber roof vent seal (weatherstrip) for models equipped with factory roof vent such as Type RA and Spec C

selector rod oil seal

Installation hardware included

PCV and EVAP systems

3rd Drive Gear TY856 6MT Ratio 1.521 REM ISF:Yes (+$40) COBB's boost control solenoid provides3rd drive gear for 6 speed manual transmissions with trans ID codes starting with "TY856". This is one of the two taller (longer) 3rd gear ratios used by Subaru for USDM STI MY07 18, Legacy Spec B, and Forester STI. It is also used in our RST F145Kit (2nd 6th long ratio) gear set with REM. Optional REM ISF (superfinishing) treatment. ISF is a precisely controlled treatment that reduces surface roughness left from the machining processes thereby