We just installed a Grimmspeed Top Mount Intercooler (TMIC) on a customer's 2003 Subaru WRX. this kit is really nice as it comes with a new TMIC, Air splitter to fit into the stock scoop, and new hoses and hardware.
The Grimmspeed kit comes with a new, larger than stock, bar-and-plate intercooler. The intercooler uses a very solid core and utilizes cast end-tanks. As with most Grimmspeed products, this intercooler is well made, and shows good craftsmanship with hand-welds. The optional hood scoop splitter is equally well made, it uses thin sheet aluminum riveted together, to give strength while being lightweight. There is also an optional piping kit, which includes new cast y-pipes, y-pipe connector, turbo outlet hose, Throttle body hose and BPV return hose. The kit does come with new T-bolt clamps for all connectors as well.
A big mistake most people make is that they buy the largest TMIC they can find, shoe-horn it into the engine bay, and call it a day. This is not the best of ideas. The Intercooler needs to be sized correctly to maximize surface area, and air flow. Air needs to be able to flow across the face of the core, as well as through it. A super thick core will not allow air to pass all the way through, reducing cooling. In order to get the most air flow over the face of the core a new splitter is necessary, with sizing to fit the new intercooler size. Using a stock splitter will only allow enough air through to cool a "stock-sized" area. Using no splitter at all will allow the air to flow around the intercooler and not through it. Both of those scenarios is not what you want.
This kit comes with a properly sized, and sealed, splitter. Which will force air over the entire face of the core, and through it. This is the ideal setup to make the most of your bigger TMIC. We highly recommend a kit of this kind, with a properly sized intercooler, a matched splitter and new silicone hoses. This will allow you to make the most of your TMIC setup, and keep your setup close to factory with better cooling over stock, without having to resort to a more complicated front mount setup.
Circuit Motorsports is a Subaru Specialist shop located in Orlando Florida. We are an authorized Grimmspeed dealer and we can acquire and install their products. We specialize in upgrading, tuning and maintaining Subaru's.