Bilstein B12 2007 Mazda 3 Mazdaspeed Front and Rear Suspension Kit

I've had the kit on my 2007 speed3 for 3-4 months now. I've owned the car since new. Before that I had the very expensive (and somewhat overrated in my opinion, at least if if you're considering it for urban use) KW V3 for almost 100,000 miles, Koni Yellows with OEM springs before that and OEM suspension when the car was new.

The B12 prokit has zero compromise. It provides almost as much control as the KW V3 but its still incredibly compliant. You can drive through the city at speed with zero fear of smashing into your bumpstops. The V3 offers slightly less body roll of course because the spring rates are 2x stiffer but you pay a huge price for that stiffness. Huge. Yes you get to lower your car down on KWs (I had the rears all the way down and the fronts so the wheels were just about to rub the wheel wells on hard turns with only me in the car) but you need to crawl through construction zones and dodge potholes in the city. In a really hard turn on really bad pavement my wheels would actually come off the ground even in the softest KW V3 settings. Yes your car will be like a sled on the KW V3s on smooth roads but on bad urban roads it's pretty horrible. Your passengers will ask if something is wrong with your car.

The Bilstein B13s cannot be lowered and I don't like how high it sits but I can cruise through a construction zone like its nothing. Speed bumps...whatever, its swallows them up. The steering is still incredibly precise and I feel total control at high speeds. No float, no extra noise. You can drive fast over bad pavement. You can drive fast through the city without wincing at every impending bump and pothole. Its incredible. Its night and day compared to the V3s. Construction zones and city driving at speed was impossible in the V3s without pounding your teeth out of your mouth and bending rims. I love the B12 prokit. If only the installation instructions were better!!!