Why is this upgrade beneficial for both stock and heavily modified Infiniti Q50 & Q60's?  Most vehicles have traditionally used an air-to-air intercooler to cool the hot air produced by the turbochargers before this hot air enters the engine.  Hot air is not only bad for an engine (hot air drastically increases the potential of detonation - bad explosions - in an engine), hot air also significantly reduces the power output of an engine.  The cooler the intake air entering the engine, the more power the engine will make.

When Infiniti created the VR30TT engine, it decided to use a water-to-air intercooler located directly on top of the engine.  By utilizing a water-to-air intercooler Infiniti was able to reduce costs and make the packaging of the engine and its turbochargers very efficient by eliminating a lot of "intercooler" piping that would have been necessary to get the air from the turbocharger, to the front of the vehicle where an air-to-air intercooler would be located, and then back to the engine.  It is common to have a total of 10+ feet of intercooler piping that air travels through in a vehicle with an air-to-air intercooler.  With the water-to-air intercooler in the Infiniti Q50 & Q60, the air coming out of the turbochargers almost instantly feeds into the water-to-air intercooler where the air is cooled, and then the air nearly instantly (within inches) is feed into the engine.  This reduction in piping allows the car to have essentially no "turbo lag" for instant engine power and response. 

How does a water-to-air intercooler cool itself?  A water-to-air intercooler needs cool fluid to pass through the "water" side of the intercooler to keep the intercooler cool.  A water-to-air intercooler uses an electric water pump to circulate fluid from the water-to-air intercooler to a heat exchanger.  The heat exchanger is basically a "revers" water-to-air intercooler.  The factory heat exchanger is located at the front of the vehicle where cooler outside air passes through the heat exchanger, and this outside air cools the heat exchanger.  The fluid runs through the heat exchanger (similar to how a radiator works). The fluid, once it passes through the heat exchanger, is "cooled" and makes it was back to the water-to-air intercooler.  This "cooled" fluid now become the mechanism that cools the water-to-air intercooler.  So when the air from the turbocharger passes through the water-to-air intercooler the air will now be cooled.

What happens when a water-to-air intercooler is not properly cooled?

Without cool fluid passing through the "water" portion of the water-to-air intercooler, the air portion of the intercooler would not cool the hot air passing through it from the turbochargers.  This hot air would not only then make its way to the engine, this hot air would itself increase the temperature of the water-to-air intercooler creating what is referred to as "heat soak".  Once a water-to-air intercooler is heat soaked not only does the engine receive air that is too hot, the fluid in the water-to-air intercooler can boil.  This boiling will create air pockets in the water system that will then cause the electric water pump to fail.

The downfall of a water-to-air system is as follows - it is much harder to keep a water-to-air intercooler cool when it is located inside the engine bay vs. an air-to-air intercooler which is located outside of the engine bay at the very front of the vehicle.  The factory Q50/Q60 heat exchanger is undersized (very small pursuant to the power capabilities of even the stock Q50 & Q60).  So when the Q50 & Q60 is driven quickly the factory heat exchanger becomes heat soaked, and this is why there is a high failure rate of the factory electric water pump.

Solution - Upgrading the factory heat exchanger with a higher capacity, better designed for performance heat exchanger.

With extensive testing, we found that the factory Infiniti heat exchanger not only does a bad job of cooling, it also restricts coolant flow.  This slows the flow of fluid though the water-to-air intercooler, which reduces the cooling of the air going to your engine, and make the factory electric water pump work harder.  Significantly increasing the internal tube area in the AAM Competition Infiniti Q50 Q60 High Capacity Heat Exchanger allows the system to run at lower pressure.  This lower pressure allows the water pump to operate under less stress and therefore increases its long-term reliability. 

In addition, our heat exchanger features an all-aluminum, TIG-welded construction for improved durability, as well as a captive bleeder valve to help with installation.