How does the number compare, though? What does a 169% increase in size look like in relation to the FK8? Well, lucky for you, the difference in size is quite notable, as it should be when we’re more than doubling the size of the stock unit. The stock unit appears as if it fills that entire lower grille opening on the front bumper. However, our engineer put in his best efforts to demonstrate that there was plenty of room to expand into.

Honda was nice enough to leave plenty of room for us to grow.

Once removed from the Civic, the size difference is much more apparent. With the 3 additional rows of fins, our new design towers, bringing a 50mm increase over what Honda deemed appropriate for their mother of all hatchbacks. Adding to the height of the new design not only helps with the new core volume figure, but also increases the frontal surface area for the heat exchanger, which is arguably just as important. Where volume and thickness allow for an increase in flow and the ability to cool more air at once, increasing the fin surface area enhances the fresh air’s ability to whisk the heat away from our intercooler. Size is an important factor when it comes to creating a new intercooler, but what’s on the inside counts just as much.

The construction is key. Gone is the convection oven known as Honda’s stock core design. In its place is our more robust, heat-wicking bars and plates. The Japanese giant did have to cut some corners when it came to their intercooling system, making a tube-and-fin and plastic combination an ideal solution for even their limited run super-hatchback. Upon release, they made it seem that the FK8 was ready to dominate the track. Stories of the contrary have been reported, though, of high temperatures from plenty of our track-going friends.

Many of you might be wondering about the CTR’s Achilles heel, which is the lack of airflow to the radiator. Given the FK8’s struggle to keep the coolant, well, cool with the stock configuration, one might think that mixing an intercooler (that’s more than twice the size) into the grille will cause twice the trouble. Dan thought the same. A front-mounted intercooler is a balancing act between maximizing the flow of charged air through the core and the fresh air flowing through the fins. 

In order to maximize cooling, we would want to give the new core a fairly tight fin density, but given the CTR’s lack of airflow to the radiator, that could be counterproductive to the overall performance of the car. Dan staggered the fin density throughout the new intercooler. The external fins keep some distance from each other, allowing the fresh air to pass through to the radiator, while the internal fins are quite friendly with each other to aid in the heat transfer.

You know how the old saying goes “it’s what’s on the inside that counts?” In the case of our Civic Type R intercooler, it’s actually a little bit of both. The outward appearance, and stature over the stock intercooler unit, is designed to contribute just as much to the performance as the more robust construction and end tank design. While all of this might look great in theory, the true fruits of our labors will be revealed on the dyno.

No one ever said that R&D was a clean job.

You might remember from our design plans post that we decided to ditch the plastic end tank construction and go with a full aluminum design better suited for the new, much more robust core. In doing so, we also changed the design on the inlet and outlet, rendering the stock piping all but useless.

We did note in our review of the CTR’s stock intercooling system that the piping was clearly devised to withstand the more demanding driving capabilities that the car was intended for. With that, the oval shape that Honda incorporated into the intercooler design was to aid in the flow of charged air through the intercooler, and make full use of the core, hence the funky looking adapters on the stock piping.

We could have easily designed our new end tanks with the stock piping in mind. However, Dan had his focus set on the future potential of the K20C1. The issue with the stock piping adapter is that their 58mm diameter  will restrict the flow to and from your intercooler, and ultimately limit the performance, especially after installing a tune. Since making oval-shaped silicone couplers is a little tricky, and recreating the aluminum adapters would be pricy, we went back to the classic circle shape all while improving on the performance.

Much like how creating a new intercooler is a balancing act, it’s also crucial that we get the piping diameter just right. Where the stock piping would eventually become a restriction, opening the piping diameter too much would cause a massive drop in boost pressure, which is just as bad as creating a choke point. Our engineer found that a 2.5” mandrel-bent section of pipe was the best option for optimizing airflow on the cold side, and adding an extra splash of color to your CTR’s engine bay.

Where our cold-side pipe is coupled with specifically designed silicone pieces, our hot side is a single section of the stuff. Using 5 layers of durable silicone embedded with heat-resistant fibers, this new hose reduces the risk of leak points and is more than tough enough for the turbo K20.

With the charged air delivery method sorted out, our hefty new intercooler makes much more sense. On paper, and installed on the car, our new design looks great, but the true test of our new intercooler kit comes after CTR #1254 spends some time on our Dynapacks.

A bigger intercooler is an investment in your Civic Type R’s future, especially for those who are doing builds and expect big numbers from the K20C1. Depending on the car and the design, adding more fins and surface area to the intercooling system usually gives you some power right off the bat. Our new design does squeeze a few extra drops of power from the CTR, but the main objective is to keep your charged air temperatures down.

Where the stock intercooler would flunk out from even spirited driving, our intercooler is designed to keep the CTR’s GPA up, and its finals week here at Mishimoto. Our engineer, Dan has plenty of testing in store to make sure that it’s up to the task. We started with standard power pulls. These single runs give us not only a look as to how well the new core can wick away the heat, but also allows us to record any power increases. For the sake of science, we made sure to run the same tests on our CTR’s stock intercooler as well. Here’s what we saw with the factory unit.

Just from looking at this graph, it’s plain to see that heat takes up residence in the stock intercooler without much resistance. The main effect is that those high temperatures are now being forced into your intake manifold, and aren’t nearly as easy to compress. By comparison, here is what our larger core and piping was able to do to keep the charged air temperatures down.

The real difference is apparent when we run our heat-soak tests. Since nobody drives their CTR one power pull at a time, we’ve devised a way to simulate the effects of demanding driving styles and heat up the core. We run 4 sustained pulls directly after each other, with no break to let the car cool. First up in the hot seat is the stock intercooler.

Honda clearly had daily driving in mind when they first developed the CTR’s intercooler. The smaller volume, and lightweight tube-and-fin construction make for easy passage of the heat from one side to the other. With temperatures reaching upwards of 140°F from the outlet on a stock tune, the K20C1’s performance is going to suffer once you really start putting the hammer down. Unfortunately, we ran our testing before any of the tuning was available, but it’s not hard to imagine that the results would be much hotter. For a little insight into what a tune can do to your charged air temperatures, make sure you check out the the data we collected when testing the intercooler for the CTR’s little brother. With the stock testing complete, we swapped out the dinky stock core for ours to see what it had to offer.

With our intercooler kit installed, we couldn’t seem to get the outlet temperature to budge much higher than the ambient temperatures in the shop. Thanks to the total increased volume, combined with the hefty bar-and-plate construction, our core design was able to intercept the heat before it made its way across the intercooler.

Heat isn’t the only thing that our intercooler kit can handle. There’s one thing that going to school and the CTR definitely have in common. There’s lots of pressure. When modding a turbocharged vehicle, it’s all about how to maximize the boost pressure. Luckily, cranking up the PSI on a modern forced induction vehicle is pretty easy by way of a tune, but as we went over earlier, the unwanted side effect is heat, hence the need for an intercooler. If you look back through our design plans, you’ll see that going for the biggest possible diameter on the piping and inlet/outlet sizes isn’t in the best interest for capitalizing on your boost pressure. Dan made sure to run all the right calculations in order to get the pipe and end tank opening sizes just right. Calculations could only get us so far, so we made sure to measure our boost pressure on the inlet and outlet of both the stock core and our core.

 

With any intercooler, even stock units, there’s going to be some sort of pressure drop. Just the nature of filling the volume and slowing the air enough so the heat can be wicked away reduces the amount of pressure recorded on the other side. You might notice that during our testing we did record approximately 1 PSI of additional pressure drop over the full system, which, given the increased size of the pipes and the internal volume of the new core, wouldn’t even cause a noticeable effect on the boost pressure.

It’s here, graduation day for our now highly educated and chilled out CTR. It’s a no brainer that the stock unit wasn’t up to the task, and our new and improved core was the degree your Type R needed to go even further. After acing the test in temperature drops, crushing the exam in pressure drops, and picking up some credits in the department of power, the CTR is ready to tackle the post-grad life of tunes and bigger turbos.