Amber Performance are an Approved Forge Motorsport Reseller & Only sell 100% Genuine Forge Motorsport products. Piston Recirculating Valve for Subaru Impreza 2001 Onwards. Alloy Recirculating Valve available to fit the Impreza 2001 onwards models including the 2009 GR Sti.Made from billet aluminium, this recirculating diverter valve dumps the charge-air back into the air intake system keeping external noise to a minimum. This increases both quicker throttle response and higher clamping load to maintain boost pressure more reliably. If you require your parts quickly then please check stock before ordering to avoid any unexpected lead time.