|But sounds are just part of the new-found pleasure this kit delivers. The real fun is in finding its phenomenal pace, which is still as silky-smooth as the regular 350Z, but offers one hell of a lot more.
Put your foot down in the first two gears and it snaps to the rev limiter, fighting for traction. These gears get your 1545kg shell moving but, in third, fourth, fifth and sixth, with the mass of the 350Z now on your side, acceleration is muscular in the extreme.
With a phenomenal 420lb ft from 3250rpm, running flat right to the peak power point over 5000rpm, this is the sort of figure most drivers can only dream of. A lot of that grunt is down to the massive cubic capacity of the engine, which helps to get the turbos on boost so quickly. Hence the responsiveness at any revs.
Planting your foot in third gear, even as low as 30mph, results in an instant push back into your bucket seat. This builds rapidly into a firm shove - and finishes off with a heady, exhilarating pull to peak power just over 5500rpm. Going up a gear at peak revs, and nailing it again, results in a repeat action of horizon hauling. And it's all so smooth and refined, quite unlike some turbo cars.
You've really got a taste of everything there - instant throttle response (rare with turbo cars), a mental mid range (rare with normally-aspirated cars) and a genuinely muscular pull at higher revs. Torque is the 3502's main weapon - and it has it by the shed-load.
And, thanks to the 3502's brilliant continuously variable valve timing, there's no lumpy cam kick-in point, just smooth power. The fact that this characteristic is maintained is testament to the thorough development - not just from APS, but also from G-Force on its Dyno Dynamics rolling-road.
But this is the G-Force way, not only bringing us Brits the best APS gear from the Australian and American markets, but making sure that the product is the very best it can be on UK-spec cars before being released here. And it is. In fact, G-Force could easily have made the 350Z develop over 450bhp, but toned down the boost to aid longevity and reliability.
A standard 3502 makes 280bhp (PS) at 5500rpm, with 2671b ft available from 4800rpm. After the APS twin-turbo conversion, it delivers 431 bhp at 5500rpm and a thumping 420lb ft of torque from just 3250rpm right up to 5300rpm. That's a rise of 155bhp and 1441b ft, the latter across almost the whole rev range.
The price? The kit costs £7370 plus a further £1762.50 to install it. That's still good value when you consider what else you can get that delivers this level of fabulous performance and style.
As Joe Czarnecki of G-Force Motorsport explains: 'It may look like a lot of money on paper but, when you drive the end result, it stands up really well against some very serious, much more expensive machinery. The transformation is phenomenal with instant pull in any gear, at any revs, and a lot more to offer right across the board, while still maintaining the 3502's smoothness.'
And it doesn't stop there, either. G-Force is currently having uprated clutch and brake kits developed, so as to offer customers an even higher level of performance, although our test drive didn't reveal any shortcomings in either area for fast-road use.
G-Force has also enrolled race suspension experts, Nitron, to help develop a range of coilover kits for the 350Z (and for the Impreza, incidentally). These are currently being; tested in Japan by an ex-NJSMO works driver. Expect the build quality to be race standard, with prices ranging from around £1300 upwards.
No doubt, further down the line, there will be a few nutters who will want to rip the big V6 engine to bits, stick in a load of forged goodies and metal gaskets and wind some more boost through the turbos or even fit larger replacement versions. Quite frankly, there's really no need, as it's is so well rounded and so capable already. You'd be better oft finding the extra pace by losing weight from the 1545kg shell.
The standard 350Z is a cracking car, with fabulous style, performance and handling characteristics. Taking a 350Z to G-Force and having this wonderful 430bhp APS twin-turbo conversion installed simply takes all those fabulous Z attributes to an altogether higher level. Now all you need do is find a 350Z.The rest is obvious..
G-Force Motorsport, Aylesbury, Bucks UK