The making of the mk4?
Hot news from Mazda – it has revised the mk4 range and given the 2.0-litre a power hike from 158bhp to 181bhp. The speed hungry should form an orderly queue, writes Brett Fraser. Photos: Dominic Fraser/mazda UK
Mazda has upped the power of the mk4 2.0-litre from 158bhp to 181bhp – but how does extra grunt affect the car’s character?
The dancing, tumbling Northern Ireland road is wonderfully free of traffic. It’s a bit narrow and a bit bumpy, but there’s a good line of sight through some of the faster corners and the 2.0-litre mk4 MX-5 feels very much at home here. The model we’re in, the new range-topping GT Sport Nav+, is fitted as standard with Bilstein dampers, and though this means the suspension is slightly stiffer – for which you should read sportier – than the standard setup, the road’s lumps and dips aren’t troubling us much, while the mk4’s narrow body grants a freedom you don’t get in larger cars to pick a good position on the Tarmac within the confines of your side of the road.
Hard on the brakes now because there’s a tight bend ahead, wishing they had a tad more initial bite and that the pedals were easier to heel and toe with, but we arrive at the apex at a sensible speed so they’re clearly doing their job okay.we’ve already snicked that stubby little gearlever forward into its third gear slot and we’re ready to floor the accelerator and eat up the emerging section of straight carriageway ahead.
As the revs keep rising there’s a gutsy snarl we don’t recall from the last mk4 we drove – the limited edition Z-sport – and without doubt the car is hustling along with greater urgency and doing so from lower down the rev range. Then the rev counter’s needle goes rocketing past the 6800rpm mark where previously its progress would have been gently halted by the engine management system, and climaxes at a heady and heartening 7500rpm, the same as the 1.5: seems like a more natural place for a zippy little open-top sports car to hang its red line
As the revs keep rising there’s a gutsy snarl we don’t recall from the last mk4 we drove
than further back round the dial, while the extra punch, well, who wouldn’t want a bit of that?
This, in case you haven’t already guessed, is the 2019 mk4 MX-5. Perhaps we should refer to it as the mk4.5, because although there are no external visual changes, bar a new paint colour for the alloy wheels, under the bonnet Mazda’s engineers have been busy, mainly with the 2.0-litre Skyactiv-g engine but also tinkering with the 1.5litre version. In these cost-conscious, microchip-managed times, it’s common practice for engine upgrades to be little more than tweaking a few algorithms, but Mazda has gone old school and attended to the mechanical parts, too.
Each of the 2.0-litre’s pistons is 27g lighter, and 41g have been lost from each conrod; the crankshaft is redesigned, as are the camshafts; there are new fuel injectors; breathing is improved thanks to a 28% larger intake throttle body combined with bigger inlet ports and exhaust valve diameters – the exhaust valves are also lighter and now activated by a high-lift cam lobe; a pickme-up for the throttle response is achieved courtesy of a low-inertia dualmass flywheel; and Mazda has finally done something about the uninspiring exhaust note by fitting a raspier silencer. Considerably less has been done with the 1.5-litre Skyactiv-g, but Mazda has reduced its internal frictional losses for greater economy and, presumably, improved throttle response.
Perhaps a little disappointingly there’s no power increase for the 1.5, and its torque rises an imperceptible 1lb ft over the previous peak of 111lb ft. Not that the 2.0-litre – despite the depth of its reengineering – fares much better in the torque department, now topping out at 151lb ft (developed at 4000rpm) against the 148lb ft of before. It’s a much better story where the power is concerned, thankfully, the peak boosted from a perfectly adequate 158bhp to a more thrilling 181bhp.
But it’s the way the revamped 2.0-litre engine delivers its power that is the revelation: it’s now as rev-happy as the 1.5 whilst flexing appreciably more muscle than either the smaller capacity unit or its 2.0-litre forebear. It picks up heartily from below 2000rpm and zings on, ever-energetically, through to that 7500rpm soft redline: maximum power is actually developed at 7000rpm, but the engine behaves so sweetly and sounds so encouraging at the top end that you’ll want to keep wringing it all the way out.
The benefits of the extra oomph can be enjoyed all along the back lanes of Northern Ireland. Because you’re not bumping into the rev limiter so early you don’t have to change gear so often, plus you’ve got more poke to play with in any given ratio. Exiting corners is where you appreciate it the most, because the additional firepower and throttle response mean you’re not waiting so long for the revs to build and you’re accelerating faster. Mazda’s official performance figures say that the new 2.0-litre engine gets the mk4 from standstill to 62mph in 6.5sec, which is 0.8sec quicker than before, yet out on the road the power gain feels better than that because it makes its presence felt across a broad spectrum of real-world driving conditions.
That’s not to say that suddenly the 2.0 MX-5 has elevated its status to that of hardcore sports car and that Porsche Boxster drivers will need to keep a keener eye on their rear-view mirrors. But in a car that still only weighs 1105kg (complete with 75kg driver), a 23bhp power increase has a greater impact than it would in other, far heavier sports cars.with a degree of commitment you could whip the old 2.0 along at very serious pace on an empty road because the chassis is so classy and agile: the revised car’s newfound throttle response makes the mk4 feel even more playful because it gives you greater control to adjust the balance of the chassis in long, fast corners. It’s not that the extra horsepower brings the chassis alive because it has never been lacking in that department, it simply gives it even
Now that you’re arriving at corners somewhat more rapidly than previously, it would have been nice if Mazda had uprated the mk4’s brakes: their initial bite is meagre and by the time you’ve realised that you’re not slowing down at quite the rate you were expecting, you’re jumping on the middle pedal. Still, that gives the aftermarket brake manufacturers something to sink their teeth into. And despite the fact that the 2.0 mk4 now has a soundtrack much more appropriate to a hot-headed sports car, the aftermarket exhaust guys will, without doubt, be able to give it more aural menace than a mass-production car maker like Mazda can get away with.
As with the exterior, Mazda has wisely left the interior unchanged visually. But
Soul Red Crystal is a new colour for the MX-5 and in sunlight really sparkles, but it’s a £790 option. Sand leather upholstery is standard on the new range-topping 2.0 GT Sport Nav+. Helping the economy and emissions of both the 2.0 and 1.5 is the introduction of a stop/start system