Japanese Performance - APS Twin Turbo Nissan 350Z (Article)
From Nissan 350Z & 370Z Wiki
When Nissan launched its £24,000, 3.5"litre V6, two-seater sports coupe, the 350Z, Audi chiefs must have spat their designer espressos across their chrome- and leather-clad boardrooms. Suddenly, their all-conquering fashion victim steed, the TT, looked old and over-priced (at £27,500) – and was also out-classed, in all areas. The 350Z had a better engine (3.5 V6 versus 1.8-litre four-pot turbo), was faster (0-62mph in 5.9 seconds, 155mph limited V-max), boasted better handling (thanks to alloy multi-link suspension and rear-drivel front-engine layout) and, arguably, was better looking, to boot.
No wonder, then, that, even today (some 18 months after its UK launch), trying to find and buy a decent 350Z is a serious mission. Demand has far outstripped supply, meaning you're doing amazingly well to find one - even with high miles and in poor condition - for less than £20K,such is its popularity, and deservedly so.
However, what Nissan probably didn't know was that it could have had other big-name flagship cars quaking in their Iow-profile rubber boots. But only if they'd spotted the 350Z's untapped potential.
Australian tuning specialists, APS (APS Engineering), realized that there was a whole lot more to come from the 350Z. Not convinced that 280bhp, 5.9 seconds to 62mph and 155mph was enough, APS engineers have designed a kit to take the 350Z out of the toddler group to play football with kids from the big school. But how do they achieve this? Two turbos, of course - what else? Official APS UK distributor, G-Force Motorsport, wasn't slow in seeing the potential for the UK market.
It must be said that Nissan's 350Z is extremely good in all areas, straight out of the box. With 18in Rays rims, a delightful V6 engine coupled to a six-speed close-ratio 'box, rear-wheel drive, a great interior and neat styling package, there's little left for the modification men to get their teeth into. Especially as we all know that tuning an already well-developed normally aspirated engine is hard work, expensive - and usually for minimal gains when compared with forced-aspiration cars.
So, the decision to develop a bolt-on twin-turbo kit is pure inspiration, especially as the resulting 400-plus bhp rivals the power levels of a 911 Turbo or a heavily-modified Evo or Scooby. No normally-aspirated 350Z could achieve this. And, importantly, the kit itself is so simple. It's designed to bolt straight onto the VQ35DE Nissan V6 engine, with no modifications to the engine internals, no compression ratio changes - not even a different clutch, such is the engineering brilliance of both the original car and the kit.
The only engine change, aside from induction, exhaust and fuelling alterations, is an enlarged APS sump (and uprated oil pump), giving a six-litre capacity of synthetic black gold. This provides the necessary extra fluid required to cope with additional lubrication of the two turbo units.
The rest of the kit, which is best fitted as an engine-out job (although it can be done on the car, you're left with less skin on your knuckles when it's finished), is all bolt-on.
The turbos themselves are simple, relatively small (and, therefore, responsive) Garrett units, bolted onto the side of each bank of cylinders, using mounting brackets and all associated pipework provided in the APS kit. It's almost impossible to see the units from above, with just the actuator and the edges of the compressor wheels visible through tight gaps with the bonnet up.
There's very little extra room in this engine bay, so it's really only the blow-off valve and hard pipe to the front-mount intercooler you can observe. Only with the car on a ramp can you catch sight of the small turbines buried away, while the extent of the fabulously engineered exhaust and induction modifications is also revealed.
APS has obviously had to develop custom manifolding arrangements for each turbo, as well as a full 2.5in cat-back stainless steel exhaust system. The twin pipes eventually meet at a combined back box, which splits into the hallmark 350Z twin tailpipes exiting at the rear.
The inner wing-mounted high-flow induction kits are also clearly visible under here, too. Buried deep in the front wheelarches, these are well isolated from engine and turbo heat, although caution must be taken when driving through deep puddles or standing water, so as not to suck any of the wet stuff into the engine, which could lead to disastrous results.
Meanwhile, with more air being pumped into the engine, the fuelling has been totally overhauled to cope with the uprated demands of the twin turbos. This means a new 255-litres-per-hour in-tank pump, braided lines, Sard pressure regulator and six 380cc injectors. Injection control remains under the watchful eye of the original ECU, as is ignition timing and variable valve timing. However, as there is no function on the standard ECU for boost pressure control, this is managed separately by an electronic boost controller, which is provided in the kit.
Finally, to aid in the reduction of turbo lag and to prevent turbo stall off-throttle, APS provides a blow-off valve. A side effect is that it also adds that quintessential turbo 'psseeu' as you go off throttle. And why not? It's never intrusive and only serves to enhance the new twin-turbo 350Z driving experience. Speaking of which - what an experience that is!
When editor Vincent drove the standard 350Z on its launch in Germany in the summer of 2004, he wrote: 'The latest Nissan coupe is one of those cars that just seems so effortless. Whatever the challenge, the 350Z faces it without flinching and just gets on with the job. This is one of those cars that somehow does everything well; it contrives to add up to more than the sum of its parts. That big, growling V6 provides much of its character but, perhaps, the biggest draw is the accessibility of its performance. The chassis is lithe and responsive and the engine wall-to-wall torque.
High praise, indeed. And this new APS-fettled G-Force Motorsport 350Z Twin Turbo is just so much better again. To summarise the feel of the new TT 350Z, take all of that quote about the standard 350Z and magnify it - twice over. Then add some - and a bit more.
The addition of this twin-turbo kit has lifted this £25K coupe into supercar-slaying territory, crucially without taking anything away from the already superb standard car. The turbochargers simply add to the 350Z's armoury, transporting it onto a new plateau of brilliance, while still maintaining all of its original appeal - just with added zest and zeal. The dyno graph shows this clearly. It's an almost exact replica of the standard car's, but with loads more power and torque available right across the rev range.
A blast out on the road soon proves it. Bury the throttle and the deep growl and burble of the V6 engine are enhanced by the induction roar and a glorious exhaust note when the blowers kick in. The mid range is simply masterful, building up to a punchy peak power pull over 5500rpm.
Meanwhile, the additional turbocharger soundtrack - with the occasional flutter of the wastegates, the on-boost whine and the hiss of the blow-off valve - makes the hairs on your neck stand on end. When you drive the 350Z with the APS turbo conversion, you wonder why Nissan didn't build it this way.
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..
