After extensive dyno and track testing, this manifold delivers the best power, fitment, and reliability over everything else on the market. It’s perfect for the K series Miata swaps, but also works for other RWD K swaps in S2000s, BMWs, Nissans, and much more. 

Features:

• Forward facing throttle body location specifically for RWD vehicles
• Built from A356-T6 heat treated aluminum to provide extreme durability
• Three liter plenum provides sufficient volume for both stock and built engines
• Comparable top end power with increased mid range torque compared to the Skunk2 Ultra Street
• 74mm inlet that accepts a B series throttle body and TPS
• K series MAP sensor port provides simplified wiring and tuning
• K series idle air control valve (IACV) port provides a factory idle at all temperatures, and is perfectly positioned to connect to an OEM engine harness without modification.
• Improved fitment in a RWD engine bay on all sides: sufficient clearance for the stock K series belt tensioner and idler pulley, and a higher plenum height to provide easy access to bolts and wiring below
• Available with or without the TSX (RBB) style water port to fit all K20 and K24 heads without any cutting, adapters, or extra fittings (RBB head flange pictured)
• Built-in throttle cable bracket mount
• Available with optional new gasket, all new hardware, and a ½” NPT to 90 degree ⅝” barbed fitting for RBB style heads.

We recommend pairing the manifold with an OEM style metal gasket only. The plastic thermal gaskets can cause bolt heads to crack off, and in some cases other brands of manifolds crack. 

If you are using a K20Z3 cylinder head (RBC) then order the manifold for the K24A2 (RBB) head as the manifolds are identical.

Use an idle air control (IACV) from a 2003-2005 Accord or 2003-2006 Element, Honda part #16022-RAA-A01. OEM or aftermarket units both work well.

**K24Z3 R40 manifolds ship with larger injector bores for the larger OEM injectors supplied with these engines. If you want the smaller K20A/K24A style injectors please specify in the special instructions at checkout.