Yea the water/air intercoolers has been tried and trued many times over the years, Just think if it as a second radiator cuz that's all it is, a heat exchanger. It wont' make more power cuz figure it this way, air temps is NOT constant, so on cooler nights you can make more power, on hotter days obviously you will not cuz hot air is harder to compress. Now with a Water based unit it will hold what'ever temp is needed to keep the car from overheating that means if your temps is steady say 260 degrees then that's the air temp that your car is going to judge your A/F ratio by when you press on the gas, stochimetric or not.