Which side of the FPR should the check valve go on? With the boost pressure screw facing my firewall, there is a nipple on each side of the fpr.. currently, the check valve is on the drivers side.. is that correct?

if you are using the HRC FPR then the check valve goes onto the port with the little adjustable valve on it. it should go where air can come out of the fpr and not go in, so blow on the check valve to see which direction that is. it doesent matter which side the check valve goes on as long as it is on the adjustable needle valve
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james

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