Originally Posted by aaronng
The head is different. Of course the 115kW k20A head is not going to flow as well as the 147kW K20A. Also, the K20A in the DC5R does not have P&P. That was in the DC2R's B18C. Intake manifold should be the one with long runners. And yeah, the intake has 3 lobes + VTEC mechanism, while the exhaust is 2 lobes and normal rocker arms.
In the end, comparing the 115kW and 147kW K20A will be the same as comparing the 118kW and 140kW K24A. It's all in the head, compression ratio, VTEC, cams, intake runners and crankshaft balancing.