Top Mount Intercooler Test Results – Part 1: OEM vs. GrimmSpeed

The moment many of you have been waiting for – top mount intercooler test results! In testing and developing a heat exchanger, there are countless bits of data to collect and analyze in order to facilitate the decision making process, but when it comes to evaluating the final product, performance can be quantified with relative simplicity. Everything boils down to temperature and restriction. The intercoolers primary duty is to lower and control the temperature of the hot charge air leaving the turbo and running through the intercooler. This is the first test that we performed on both the stock unit and the GrimmSpeed unit.We setup this test to simulate a real world scenario that’s typically demanding of an intercooler. The test vehicle is a 2012 WRX with a GrimmSpeed downpipe, boost control solenoid, prototype intake and tuning. On a closed course, we accelerated in 3rd gear from 3000rpm to redline repeatedly, with 5-8sec between runs. Temperature was logged via k-type thermocouples between the turbo and the intercooler and between the intercooler and the throttle body on both units. Ambient temperature here in Minnesota for both tests was between 20 and 22 degrees F.The results above speak for themselves, but here’s a breakdown. The phase differences between the runs are a result of how quickly we could safely get the car back down to speed for another run, but the important thing to notice is the magnitude of the temperature fluctuations. Predictably, both intercoolers were seeing similar Pre-IC temperatures on each run (180-190F peak), but while the GrimmSpeed TMIC kept Post-IC temperatures between 30-40F the entire time, the OEM TMIC fluctuated between 35-75F. This is the kind of consistent cooling that you should expect from a high quality TMIC and is a function of the geometry and design of the bar and plate core. Our high density core has a massive heat transfer surface area but maintains a large enough cross-sectional flow area that there’s no added restriction.

What’s Next – Pressure Drop, Aftermarket TMICs and Warm Weather Testing

The second part of our final testing will be to measure the pressure drop across each intercooler to demonstrate that the increased cooling performance comes with no sacrifice in flow rates. We’ll also run the same tests with a couple of other aftermarket TMICs. You can expect to see these results in the coming week. Lastly, in the spring, we’ll complete all of this testing again in warmer weather to show that the same effectiveness can be expected, regardless of ambient temperature. We’ll also try to find it’s limits with our 600whp STI.