Serious drivers looking for GrimmSpeed horsepower results have to weigh which parts make sense for their cars. There are several options a Subaru owner has to take into account before upgrading their exhaust system. If they already have installed a catback exhaust, unlocking GrimmSpeed horsepower results can be achieved with the addition of a downpipe. Sometimes, it may take more. Racers who compete on the pro and semi-pro level may need an entire Subaru turbo exhaust system. This can involve adding several pipes to achieve massive airflow. The kind of GrimmSpeed horsepower results these drivers need are different from those who race as a hobby.
Overall performance benefits differ, depending on exhaust needs. Grimmspeed aftermarket pipes are available in three primary categories: Down pipes, up pipes, and crosspipes. The important thing to realize is that all of these parts are designed to lessen restrictive airflow that comes from the factory setup. Grimmspeed aftermarket pipes, in general, present wider diameter tubing which provides more room for exhaust gases to flow through. In addition, they also offer support for other systems. For instance, an Impreza up pipe aids in turbo spooling to initiate a faster response.
Most drivers rely on one specific part to begin the custom process. Subaru custom downpipes are often the first upgrade purchased. These are installed by bolting into the OEM or replacement exhaust. Essentially, what Subaru custom downpipes are responsible for is erasing the stock catalytic converters. Tasked with filtering out dirty exhaust gas, the cats hold up airflow. Replacing them with a Subaru custom downpipe eliminates this restrictive influence. In turn, exhaust flow increases along with horsepower and torque. When it comes to Grimmspeed aftermarket pipes, this is one of the most popular products.
Overall performance numbers can be difficult to pinpoint due to numerous factors. Some claim different results. If a Subaru custom downpipe is installed in a car that has an improved turbo, there can be an increase of up to 15-20 horses. With the stock turbo still in place, most report an extra 10 HP or thereabouts. It all depends. If you are an active driver with many custom parts, a complete Grimmspeed performance exhaust can offer very large gains, some as high as 40 HP.