If you own a Focus ST, Garrett Advancing Motion has come out with a new outstanding bolt on performance intercooler upgrade for your car. We obtained a sample of the intercooler for testing at the palatial MotoIQ megashop to perform dyno power and thermal testing to see how effective this unit is.
We like intercooler upgrades, they are a modification that actually gives you something for nothing. Usually, a more effective intercooler can give you more power by improving intake air density as well as less thermal stress on the engine via cooler intake air temps. Cooler temps, in turn, mean less combustion temperature and thus the engine will be farther from the edge of detonation under boost. Water and oil temps can drop. A good intercooler will also have less pressure drop across the core which means that the turbo’s compressor doesn’t need to work as hard to produce the target boost pressure. This means the turbine does not need to recover as much power from the exhaust stream to power the compressor. Less power recovery needed means less backpressure. Less backpressure means less propensity for detonation causing heat retained in the engine as well as better volumetric efficiency. With a cooler intake air temp and less backpressure, the engine’s tolerance for detonation increases which can be exploited through tuning by running more boost pressure and or ignition timing and perhaps a leaner air-fuel ratio to produce even more power.
So for a simple part, an improved intercooler has a cascade effect for making more power while reducing stress on the engine, something we can all appreciate.
The Garrett intercooler uses a bar and plate type core. Bar and plate intercoolers have a lot of thermal mass and can quickly soak up a lot of heat. The core also has internal turbulators which help heat transfer to the outside of the plates.
To aid flow and get the best radius possible from the charge pipes to the core, Garrett used cast end tanks which can have a much more complex geometry than parts fabricated from sheet. All of the welding is strong tig.
Fords tend to have condensation build up in their intercoolers, even on the OEM side which is a known problem. Thus the Garrett intercooler has a built-in drain plug so any accumulated condensation (a known Ford problem) can easily be removed without removing the intercooler from the car.
The Garrett intercooler has the correct bracketry for an easy bolt in. It will fit just like the stock intercooler!