ARC Intercoolers for the R35 Skyline are direct OEM replacement.
The stock units are a good design for stock, but become a restriction
to flow at higher HP numbers. As as the motor makes more power it
generates more heat, over powering the flow and cooling capacity of the
stock units. If you plan on doing any track driving, drag racing, or
making more power then stock, then the ARC intercoolers are for you.