Here is a kit to equip your K-series with Honda’s finest intake manifold design, and along with it, a Hybrid Racing package to make it work with your K20A/A2/A3/Z1. Note that coolant passages will need to be cut off to make the intake fit on these cylinder heads.
The RBC manifold outperforms the PRB and PRC at almost all parts of the rev range. There is a marginal power loss in the low to mid revs, but from 5500rpm onwards the RBC is a clear favorite. The dyno graph above shows the difference. The red line is the RBC manifold and blue is the PRB. The PRB makes power to 7400rpm before falling off while the RBC keeps making power all the way to redline.
The RBC intake manifold comes with a drive-by-wire throttle body, meaning if you want to retain the drive-by-cable system for your K-swap or K-equipped vehicle, you will need an adapter. Our K-series Throttle Body Adapter addresses this problem by letting you use a PRB or PRC (K20A2 Type S and K20A Type R) style cable actuated throttle body on an RBC manifold.
All hardware is included with the adapter plate. Plates have a 64mm bore for OEM sized throttle bodies.
To ensure you won’t have any leaks, we are providing the necessary gaskets including an Intake Manifold Gasket and throttle body gaskets for both the RBC and PRB/PRC sides of the adapter. These are all high-quality Hybrid Racing Thermal Gaskets that exceed OEM quality. The intake manifold gasket is machined from a thermal-resistant polymer, preventing heat transfer from the cylinder head to the intake manifold. Likewise, the throttle body gaskets also help reduce heat transfer and feature a removable insert to go from 64mm > 70mm bore size (for aftermarket TBs).