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Chase Bays Upper Water Neck and AST Delete - Mazda RX-7 FD 13B-REW



The Chase Bays Upper Water Neck AST Eliminator for Mazda 13B-REW is designed for those wanting to eliminate the terribly ugly OEM or other aftermarket Air Separator Tanks, simplify their cooling system with something much more efficient, add clearance for larger turbo, easily change the connection type (OE Push on, -16AN, -20AN), and improve engine bay aesthetics.

Our Upper Water Neck adds 1" (25.4mm) of height over stock for a better bleeding process. It features two ports on the side, one for the Factory Coolant Level Sensor and one 1/8 NPT port for accessories or fluid feed to Turbo. The Coolant Overflow outlet is 1/8 NPT threads with 1/4 Hose Connection. It faces toward the engine for a more minimalist look. We highly recommend the Chase Bays Coolant Overflow with Type 3 Bracket. This product INCLUDES the Chase Bays 20psi (1.37 bar) Radiator Cap. Most aftermarket caps for 13B are only 18.9psi (1.3 bar).

This product has been rigorously tested on Road Race, Drift, and Daily Driver RX-7's. Each were driven as intended with not one single issue occurred in the months of use and no development change was needed. The individual pieces are machined from 6061 Aluminum with special keyways to ensure 0º alignment, Tig Welded together, then Hard UV Proof Anodized Chase Bays Signature Black.

We have made the outlets keep the OE angle to ensure clearance with large pulleys. The outlet is threaded with -20AN female ORB threads and we made adapters to cater to 99% of applications. This is another feature that no other company is offering. The adapters are offered in:

• 1.5" OE Normal Push On Hose Connection
• -16AN (1" inch inner diameter)
• -20AN (1.25" inch inner diameter)