STI Performance Exhaust Vs Stock – Comparison Review

STI Performance Exhaust Vs Stock – Comparison Review

Subaru first introduced the 2.5-liter turbocharged Boxer engine in 1988, but it has been going from strength to strength, powering some of the best all-weather cars, the WRX and STI.

These cars have been game-changers in terms of overall performance – especially torque and power – pushing STI performance even further. The smooth driving characteristics of Subaru put them above many other high-end sport saloon cars with their trademark boxer rumble, yet the ride remains as gentle as a luxury car.

The Subaru Impreza WRX STI is a high-performance car with plenty of bells and whistles to satisfy gearheads without sacrificing comfort. With all the optional extras available, many people wonder if the STI performance exhaust is worth it, or whether you should just stay with the stock exhaust…

Best Performance Exhaust Systems

There are as many options for performance exhausts as there are models of performance cars, so it’s vital that you pick the right exhaust for your vehicle if you want the best results. As an established manufacturer of performance cars, Subaru offers some of the best performance exhaust systems on the market, especially if you want a system direct from the manufacturer.

STI Performance Exhausts

The Subaru STI Performance Exhaust is backed by a limited lifetime warranty, making it a highly desirable add-on for Subaru STI owners. It’s an exclusive, catalytic converter-less system that delivers all of the performance without the drone. The oversized stainless-steel muffler and tailpipes produce a throaty, deep sound that will turn heads wherever you go…

There are two types of Subaru exhaust. The catback, which includes the main section of pipe beyond the cat and muffler, and the mid-pipe, which is the smallest section of piping between the headers (or downpipe) to the midsection in front of the cat (muffler).

These two components make the STI performance exhaust. They come in three major variants: Spec C, Spec C Aero (2009-2011), Legacy GT Spec B.

STI Performance Exhaust Specs

The STI performance exhaust gives your Subaru an aggressive, low-rev sound that’s a perfect match for its sporty lines. This race-inspired system features mandrel-bent aluminized steel tubing and muffler packing to ensure peerless sound quality, durability, and power, plus the easily welded design makes installation a breeze.

STI performance exhausts feature two slip-on mufflers and sporty, free-flowing exhaust tips that increases horsepower and torque with a mellow sound that’s sure to appeal to enthusiast drivers. With US-made SS304 stainless steel construction including hangers for ease of installation, this high flow performance system is a great pickup for an awesome upgrade!

STI Performance Exhaust Review

This exhaust system is made from high-quality stainless steel, designed to perform at the highest level in naturally aspirated or forced induction applications. In addition, this 1 7/8″ cat-back exhaust features STI’s distinct T304 stainless steel tip for a clean finish, a dimpled surface to increase heat dispersion, and double-walled tips with bead blasting.

The STI performance exhaust system produces amazing power gains by allowing more airflow into the engine, increasing horsepower and torque while maintaining a deep one-of-a-kind exhaust note. With sporty, top-mounted twin tailpipes, this system improves the appearance of your car and delivers a powerful, throaty roar.

The STI performance exhaust system is a great way to increase the horsepower and overall viability of your Subaru, with four configurations to choose from: You can opt for the external wastegate, full 3-inch true short exhaust, full 3 inches true with resonator, or the 3 inches true with a short muffler.

Ideal for a vehicle that already has a free-flowing exhaust, the STI system comes complete with a downpipe, mid pipe and muffler allowing for ‘bolt-on and go’ installation. Designed to be as quiet and efficient as possible, the straight-through design minimizes backpressure to save horsepower, reduce exhaust temperature, and creates a smooth sound that can only be achieved with a free-flowing exhaust system.

How Much Power Can a Stock STI Engine Handle?

The short answer is: “A lot more power than you can safely make with a stock ECU!” We proved this by installing our high flow catalytic converters on the engine of an otherwise bone factory Subaru STI and turning 8400RPM redline.

The result was a 470whp/526lb-ft torque rating on 91 octane basic petrol. And since most turbo cars only see 30-60% of their maximum power in daily driving, there’s no telling how much power your car could make with a performance exhaust like this system.

Featuring a tuned mid-pipe, cat-back exhaust, and a modified air box with proprietary filters, this bolt-on system delivers the best power gains on the market for your Subaru. All of the STI cat back designs feature large diameter mandrel-bent T304 stainless steel piping along with heavy-duty TIG welded 304 stainless steel mufflers to produce greater gains in power handling over stock exhaust.

STI Performance Exhaust vs Stock

The STI performance exhaust system was designed from the outside in for the ultimate balance of power and sound. The outside has durable a Grade 9 brushed finish, while the inside features full coverage heat shields and mandrel bent tubing with three-bolt flanges for a slip-fit, clamp-on installation.

Not only does this exhaust give the car an aggressive sound that turns heads, but it also offers a 16% increase in power and torque at the wheels. However, it’s important to note that this exhaust is a direct fit application for the WRX sedan only.

Bottom Line

Get the best performance from your Subaru WRX STI with this short-ram performance exhaust kit. The STI Performance Exhaust is recommended for all high-performance driving as it provides a more complete flow for maximum power gains.

Additionally, the 2.5″ piping has a larger diameter for greater flow and less backpressure than stock to maximize power. The exhaust note is slightly more aggressive at wide-open throttle than stock and still maintains the non-intrusive nature Subaru enthusiasts love.

Unlike other kits that require a welded muffler, this kit bolts directly to the stock turbo inlet pipe and comes with full stainless-steel construction. For simple and instant performance-enhancing kits, it doesn’t get much better than this.