Spool Bus: The '07-'09 Mazdaspeed3

Common Issues

Heavy carbon buildup can form quickly on the intake manifold, ports and valves. To explain why this happens and how to prevent it, here’s a quick refresher on blow-by:
When the engine is running, the pistons are happily moving up and down in their cylinders. However, a small amount of combustion gas inevitably slips past the piston rings and into the crankcase.

This gas, called blow-by, accumulates and creates enough pressure in the crankcase to slow down the pistons and cause oil vapors to build up and make the oil frothy. Condensation can get trapped in the crankcase, too, and you don’t have to be a rocket scientist to know that water and oil don’t mix.

For the last 20 or so years, all new cars have featured some sort of positive crankcase ventilation system that sucks out these unwanted vapors. And instead of simply releasing the blow-by into the outside world, the PCV system carries it back to the intake manifold to be reburned.

However, this creates the potential for buildup in the intake manifold, dirty valves and poor compression. It’s especially a concern with direct-injection engines like the Mazdaspeed3’s: Unlike port-injection engines, they don’t benefit from jets of fuel rinsing carbon buildup from the intake valves.

That’s why an oil catch can is so important. It’s designed to “catch” contaminants from your crankcase and PCV system and prevent them from entering your motor.

Struts and shocks on the Mazdaspeed3 are normally good for around 40,000 miles, depending on the local roads. Good news is there are plenty of suspension options out on the market.

CorkSport offers adjustable shocks and struts, as do Koni and Bilstein.

The rear engine mount will most likely be shot. The rubber starts to tear over time, which can result in a banging sound through the floor under hard acceleration and shifting.

The OE steering wheels are showing their age–especially in the first-generation models, which are close to 10 years old. The leather is starting to wear and the stitching is starting to fray. CorkSport’s replacements for both the first- and second-gen cars have larger grips and flat bottoms, which really improves the driver experience if the stock wheel is worn out.

Basic Essentials

Ask any Mazdaspeed3 forum about must-have mods, and the members will list the following:
Cobb Accessport or VersaTuner: This software allows you to change the fuel mapping and log data from the engine ECU. It’s crucial for diagnosing Mazdaspeed3 problems and making adjustments for any future power modifications.

High-Pressure Fuel Pump Internals: The engine-mounted, high-pressure mechanical fuel pump that came with the car is great–if your motor is stock. It cannot keep up with many modifications. These upgraded internals are required for any power modifications.

Get a Tune: If you aren’t familiar with tuning cars, there’s a wide range of e-tuners available for the Mazdaspeed platform. We recommend taking a look at tunedbynishan.com, hypnotictuning.com or pd-tuning.com as examples.

Replace the Rear Engine Mount: The stock mount does not handle mods well, so a stronger one is highly recommended on a stock Mazdaspeed3.

Nice-To-Have Mods

The Mazdaspeed3’s shopping list of nice-to-have mods looks a lot like any other turbo car’s: intake, exhaust, downpipe, upgraded intercoolers.

Some companies offer staged parts packages. CorkSport’s Performance Stage 1 power package includes a CorkSport cat-back exhaust, CorkSport Stage II Short Ram Intake, and CorkSport rear motor mount. If you want to take it further, the CorkSport Performance Stage 2 kit includes the Cobb Accessport, CorkSport high-pressure fuel pump internals, and CorkSport catted downpipe.

Track Necessities

Brakes are an important improvement for the track. Even with the stock ’Speed3 power levels, improving the brakes is key to enjoying the day. A good set of track pads is recommended, along with a brake fluid upgrade to something that can handle higher temperatures. Stainless braided brake lines are good to have as well.

An upgraded rear anti-roll bar with some adjustability is a big plus as well. The Mazda3 has understeer tendencies that get exaggerated by the torque the Mazdaspeed3 makes. The upgraded rear bar makes the car more neutral in cornering, which allows the driver to focus more on corner speed instead of managing understeer.