Because this unit has 2.25 inlets and outlets, the actual power rating is limited by the in/out diameters. The cut off for the 2.25 tubes is about 600hp on a modern 4valve, 4cyl engine. As such, on the SRT this unit is rated at 600hp. Because of the 600hp flow capacity of the 2.25 in/outs the intercooler core will never see 1220 cfm. Because the 78% efficiency is derived from the amount of heat in 1220cfm of air at 325deg, the efficiency rating is lower than what will actually be the case in practice. We have observed charge air temps of 115 deg on cars that run 18psi on the stock turbo.
For applications over 600hp, check out our "Hoss" Intercooler kit for the SRT-4