APS Intercooled Twin Turbo
Twin Intercoolers
 

 
 

 

APS Twin Intercoolers

If the turbocharger can be described as the heart of the system, then the intercoolers must surely be the “lungs”!! APS has designed and manufactured a matched pair of custom configured, vertical flow high efficiency intercooler utilizing custom designed light weight cast aluminum end tanks. Extremely high charge air flow rates and massive temperature reduction - a level of performance that other manufacturers can only aspire to achieve.

Another stand-out feature of the APS intercooler system is that the stock air conditioning system is retained and unencombered. By specifying two large intercoolers, a generous air-gap is maintained to channel ambient air flow into and through the air conditioning and engine cooling radiators.

With a huge 10" x 11" x 4" core in each of the two intercoolers, target pressure drop is less than 1.0 psi and under the same turbocharger flow conditions, the intercooler outlet temperature is less than 15°F higher than ambient, at any vehicle speed over 50mph. Truly outstanding results at such a huge horsepower level. So just like the APS turbochargers, the APS intercooler has massive additional headroom available.

Vertical flow inside the APS intercooler is by far the optimum configuration given the space considerations that must be accounted for in the front of the vehicle. The intercoolers are also used to transfer chilled charge air to the throttle body area, thus minimizing the total length of ducting.

The vertical flow configuration as specified by APS spreads the charge air flow evenly over a great number of internal passages and results in excellent flow characteristics. The net effect is massive charge air temperature reduction but with high air flow.

Importantly, the APS intercooler uses the latest in Bar and Plate core technology, not low cost off the shelf tube and fin. Other than the fact that the APS intercooler core boasts the highest flow and greatest temperature reduction, the bar and plate construction results in an inherently strong intercooler core of high thermal inertia. The advantage here for the performance street car and drag race enthusiast is that with each intercooler core's high thermal inertia, massive reserves of cooling capacity are available in situations where ambient air flow over the core is low. So, after a power run to heat tires prior to staging for a quarter mile pass, there is plenty of intercooler capacity to launch with full power at your disposal - rather than forsaking power with a tube and fin construction core that becomes heat soaked during the initial burst.

Another aspect worthy of consideration is the internal air passage cross sectional area and fin arrangement of the APS Bar and Plate construction in relation to tube and fin. The tube and fin core has a 5mm edge boundary so for say a 3.5" thick core, half an inch of internal thickness is lost - which impacts on passage cross sectional area. In addition, the fins are extruded so they are essential in a straight line and parallel to flow. This means that the internal surface area presented to the charge air is nowhere near as great as that on a traditional bar and plate that has an alternating offset internal fin arrangement. The result is the bar and plate core used in the APS intercooler flows better and removes far more temperature than the traditional horizontal flow tube and fin. These are just some of the reasons for APS specifying this vertical flow bar and plate core on the Corvette TT.

Unlike other systems that require cutting or removal of structural components at the front of the vehicle, APS has designed the Corvette's FMIC system as a truly bolt-on unit that not only maintains the integrity of the vehicle, but also delivers outstanding intercooler performance.

In addition, the dual intercooler design of the APS intercooler system allows for the ultimate in true equal length balanced ducting from each turbocharger to the intercooler.

Ducting length is critical on the Corvette in order to achieve balanced induction and excellent driveability. By designing the turbocharger to intercooler ducting specifically to be of equal length, each turbocharger experiences exactly the same effective air path to the intercooler and results in totally balanced turbocharger performance. Other systems that are designed with unequal length, experience boost pressure and air movement issues where under certain conditions, one turbocharger pushes air back through the intercooler and into the other turbocharger's ducting. As air movement is momentum based, this is simply wasted energy that should be better put towards producing horsepower, not restriction.

The advanced APS dual intercooler system not only solves this problem but allows APS to utilize true equal length ducting - the most efficient routing for the twin turbo Corvette!

The APS intercooler core is of internally finned construction and offers significantly enhanced flow and heat exchange performance, particularly at high charge air mass flow rates. Also, unlike other manufacturers of intercoolers who reduce cost by using low cost off the shelf cores, the APS intercooler is designed with the optimum ratio of intercooler core surface area to intercooler volume. The result is an intercooler system with outstanding flow and cooling performance, particularly at high engine horsepower levels.

However, there is more to intercooling than size alone. Fully engineered light weight, cast aluminum end tanks ensure optimum charge air distribution throughout the entire cooling core for maximum charge air cooling and minimum pressure drop.

The reality of intercooler excellence in terms of performance equals:

  • Largest intercooler surface area possible
  • Optimal intercooler internal passage volume
  • Lowest possible pressure drop
  • Highest possible intercooler core efficiency
  • Matched to the turbocharger air delivery in lb/min

In other words the greatest possible charge air temperature reduction with the lowest possible pressure loss at the rated flow of the turbocharger.

An intercooler drops the charge air temperature, which enhances the combustion of the air/fuel mixtures. This more complete combustion of air fuel mixtures produces higher engine power.

Intercooler performance is measured by the amount of energy (temperature) the intercooler can remove from the inlet charge air as well as the pressure drop across the entire system. It is important to consider the entire intercooler system and not simply the intercooler core itself.