In deciding to go with an air-to-water intercooler setup, there are extra component and packaging challenges compared to a typical air-to-air setup. The S2000 already has a tight engine bay as Honda did an excellent job at optimization. In order to make some more package space, we needed to make a couple upgrades.
If you recall from our initial packaging trials, the air-to-water intercooler didn’t fit quite as nicely as I’d like.
Way back in the day, around a decade ago, we installed a Koyo radiator that was 53mm thick. Koyo’s newer variant is only 36mm thick. So that gets us back 17mm, or ~0.67 inch.
Koyo makes a high quality 1.3bar radiator cap. I recently handled another aftermarket shiny radiator cap and the internal gasket fell out. What a piece of garbage. And it was more expensive. Project S2000 AP1 inherited my old Koyo and the original Koyo cap is just fine.
Koyo says 36mm thick. 36.12mm is pretty damn close. A typical sheet metal bending tolerance is 1/32nd of an inch which is ~ +/- 0.8mm. So being +0.12mm is way under typical tolerance.
The stock fans bolt right up. The smaller left fan is the A/C fan and the right is the radiator fan.