SUPER SQV (Super Sequential Blow-Off Valve)
The HKS SQV is a pull type relief valve, unlike other blow off (dump) valves which are push type i.e. diaphragm AND piston types. The SQV is actuated by pressure alterations only, ensuring quick valve response and complete closure during idle. Standard dump valves must utilize large valves in order to accomodate high boost applications.
However, these large valves react slowly and require high activation pressure to open. Smaller, fast reacting valves do not permit the air flow required for high horsepower. The SQV incorporates both for maximum performance. It is engineered utilizing a small primary valve for ultra quick activation along with a secondary valve for additional relief capacity. The SQV is made of billet aluminium and emits a unique aggressive sound. (It has been mentioned by several magazines to be the best sounding valve on the market!)
It is also the only valve to work without fault on vehicles using metering units ahead of the plenum (such as found on the Ford Escort RS Turbo range), due to it keeping fully shut when on idle. They also remain shut on cruise, when there is vacuum present in the inlet manifold, although the engine is not on idle. This also prevents fuelling problems. In addition, it needs no fancy setting up such as playing with different spring pressures or limiting the air supplied to them by crude bleed valves. They simply work as a dump valve should. Straight from the box.
For drivers wishing to have a less intrusive sound when activated, HKS produce an insert which quietens the note without restricting air flow. This simply fits in place of the original 'Tri-insert' by removing 4 hex-head bolts.
Complete SQV kit (nearly all Japanese applications) £245.00
SQV valve only £185.00
SQV alloy mounting flange (for universal use) £15.00 SQV 'quiet' insert £13.95
