you just plug up the return hose, mount the valves on and add washers till your car won't stall at idle. the more washers you add the stiffer the spring and the "crisper" the sound.

i prefer the greddy typeS though. they cost more, but you tune them simply with a hex screw rather then opening the valve and dumping in washers every time. saves time and i think they look better if you don't mine the anodized purple.

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