The new generation Mazda 3 MPS – technical review
This technical review is aimed at the existing MPS community; it assumes you’re already familiar with the first generation Mazda 3 MPS and focuses on what is new for the 2009 model.
In the lead up to its Australian launch, OzMPSclub was invited to sample the new generation Mazda 3 MPS at the Sutton Road circuit just outside of Canberra. Targa Team drivers Rick Bates and Brendan Reeves were on hand to show off a bunch of new MPSs, and to show us how to get the best out of them.
I could save you a lot of reading and just say the new generation Mazda 3 MPS is bigger, stronger, faster, more economical, better equipped and costs about the same as the previous model. That’s it in a nut shell. Or, if you like details, read on, as I have lots of details to share.
The preview photos that have been floating around the web have prompted a fair amount of debate about the looks of the new 3 MPS, so lets deal with the styling first.
It’s not all about fashion. There are sound engineering reasons that contributed to the styling. The clay modellers spent 304 hours in the Miyoshi wind tunnel optimizing the shape millimetre by millimetre to minimise turbulence and eddies on each part of the body. The grille opening is 70% of the previous model’s size and the frontal shape directs unwanted air smoothly over the body. There’s also a reason for the shape of the bulging rear tail lights, which provide a cleaner separation of airflow and reduce drag-inducing eddy currents around the back of the car.
All the design effort has resulted in a body shape that cuts through the air more quietly and has a coefficient of drag that is down from 0.34 to 0.32. The improved aerodynamics are also responsible for the official fuel consumption figure dropping from 10.0 L/100 km to 9.9, which would add up to a few bob in your pocket over the life of the car. For Dashhawk users, the frontal area is 2.217m2.
While we’re discussing aerodynamics, no one will have missed the bonnet scoop that feeds the top mount intercooler. The stated aim of the new scoop is to reduce heat soak, allowing more consistent engine output. It also frees up grille space for more fresh air to be ducted to the intake.
Beyond the intake is essentially the same turbocharged direct injection engine and intercooler as before, still delivering 190kw and 380nm of torque. What has changed is the intake volume and boost pressure control that “suppresses sudden torque peaks for smoother, more linear torque characteristics.”
The gearbox has a taller 6th gear ratio for a quieter ride and improved fuel economy on the highway. In fact all the gears are taller, with ratios chosen so when you flat change at 6,000 rpm, the engine is dropped right back into the sweet spot of the torque curve. The shifter is moved closer to the driver and slightly higher. Outboard of the gearbox are stiffer axles which are intended to minimise torque steer.
The new car is slightly heavier, but the body shell itself is actually lighter. So how does a body that’s bigger and stronger get to be lighter? The entire car was given the Jenny Craig treatment with a “gram-by-gram” weight reduction program. The greatest single reduction came from increased use of 1,480 MPa ultra-high tensile steel, saving 11kg.
Body rigidity is a big deal when it comes to handling, and Mazda have paid a lot of attention to it. The list of strengthening changes is huge and includes additional spot welds, larger corner radii, stronger gussets, larger tunnel, stronger joints to the rear suspension towers and strut bars on the front towers. The result is a 48% improvement in diagonal displacement around the tailgate area. It also translates into an 11% improvement in NVH levels. But don’t ask for a sunroof, the engineers don’t like what a sunroof does to body rigidity, so it’s not on the options list.
Mazda is aware that the FWD platform of the 3 MPS could earn it some demerit points against RWD and AWD competitors and have gone to a lot of effort to provide a car with better handling balance, greater ability to get the power to the ground, and importantly, advice on the correct driving technique to get the best from this car.
The big news in the suspension department is revised spring rates which are softer at the front and firmer at the rear. These changes are aimed at improving the handling balance. And they work; chucking the cars through the undulating back section of the Canberra circuit under the expert tuition of Rick Bates revealed that a bit of trailing brake going into some corners will help the car retain a neutral balance. From there, it’s possible to induce some over-steer which allows you to get on the power earlier and find a much quicker way through the corner. Enthusiasts may no longer need to put a larger rear sway bar near the top of their mod list.
Speaking of sway bars, the mounting span has been increased to improve roll linearity, and there is also a stronger cross member, thicker cross-arm and the bushes have been optimised to improve lateral rigidity. There’s that word again!
Driver input is via a new electro-hydraulic power assisted steering system (aka EHPAS), which adjusts control to vehicle speed and steering angle. As a free bonus, there’s a reduction in the amount of power being robbed from the crank by the power steering pump.
There are larger wheels and tyres to compliment the new suspension, with 18 x 7.5 RX8 style rims running 225/40/18 Dunlop SP Sport 2050s. Not only do you get more rubber on the ground, you also have a bigger and cheaper range of tyres to choose from when you need new rubber, compared to the rare and expensive 215/45/18s of the previous model. Brakes remain unchanged simply because they’re so good they don’t need improving.
So how does it perform? Testing the all important 0-100 km/h turned in a best of 6.1 seconds, however 6.3s can be done consistently. But like previous MPSs, the in-gear acceleration is where this car really does the business and it will still blow the doors off a BMW M3 accelerating from 80-120 km/h in any gear. What that means on the road is phenomenal overtaking ability.
There’s not much that hasn’t already been said about Mazda’s torquey direct injection turbo engine, but if you like the effortless push in the back from any rpm like a V8, without the high fuel consumption, get an MPS. With all that torque available - changing gears is optional.
Like I mentioned earlier, the technique for getting the best from the 3 MPS is to keep it balanced and keep it smooth. Chose your lines to straighten the car up as much as you can between corners. In the words of Rick Bates, “brake in a straight line, power in a straight line.” Although it’s usually true for any car, our laps on the skid pan proved that the most unspectacular laps were the fastest.
Brendan and Rick demonstrated that leaving the DSC turned ON is not only safer, it’s also quicker in terms of lap times. That’s useful information transferable to the street. It’s also your evidence that there’s nothing to be gained by turning DSC off.
My only criticism is the change to twin exhaust outlets. It seems the stylists finally scored a win over the engineers. There’s no need for an inline four cylinder engine to run a twin exhaust, except for the wank factor. It adds weight, it adds cost and the t-piece at the split would not flow as well as a straight single pipe.
So that’s one cross in the negative column and a whole bunch of crosses in the positive column. The 3 MPS just got a whole lot better. If you’re worried about the styling, don’t be. It took me about half a day to get used to it, and trust me, it looks a lot better in real life!