The RRC Intake manifold has been voted the best oem intake manifold for the K-Series Engine. Found on the FD2 Civic Type R, this intake manifold takes its design from the previous RBC but has been fettled to give the K20 engine a refined and more powerful bolt on gain. Although externally being very similar in shape, the RRC has an slightly enlarged plenum, enlarged intake runners and has been mildly polished internally. In head to head intake manifold shoot outs, the RRC seem to consecutively come out on top with its emphasis on mid to high power, it is the perfect manifold for N/A and Boosted K20 applications. It is also a direct fitment for the k20z (fn2) and can be easily modified, exactly like the rbc, for fitment on the older k20a/a2/K-swaps. This is also available pre-cut and with a throttle body adapter. Please enquire. Genuine Honda Unbeatable Quality and Fitment. An RRC Specific throttle body adapter is also needed to use k20a mechanical style throttle. Please see inlet adapters.