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Hardcore E46 M3 islightened and treatedto velocity stacks forultimate fast road use…

FULLBODIED

E12 5 SERIESTastefully modified classic:

Gorgeous 528i is beautifully reworked

WINHalfords

p22Tools

DRIVEN:SUPERCHARGED E39 M5

E36 TOURINGS:TheUK’s infamous Atlantis blue duo

FORZAParis to London

in an F10 M5

CAR OF THE YEAR

Vote now for your starBMW of 2012

FC PBMW 0113 22/11/2012 10:42 Page 1

PRODUCT FOCUS:EVOLVE STAGE 2

SUPERCHARGER KITFOR THE E39 M5

We road-test Evolve Automotive’s Stage 2 supercharger kit for theE39 M5 to see if it delivers the performance we hope it will…

Words: Andy Basoo Photos: Stephen Hall

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THE ISSUE

At launch, the E39 M5 receivedrave reviews. It was the bestrendition of the model to date.The primary reason for the highpraise is the S62B50 engine

under the bonnet. The 4.9-litre V8 was anevolution of the 4.4-litre M62B44 (as found inthe 540i) and produced 394bhp. BMW listeda 0-62mph time of 5.3 seconds, but a numberof publications found that 62mph came up afew tenths quicker in their independent tests.

It was, and still is, a special engine. But isit perfect? No. The S62 produces its torquevery early on, hence its phenomenal pace.

However, past 5000rpm, despite the V8 beinghappy to keep revving for another 2k, torquestarts to drop off quite quickly. The facts andfigures prove the M5 isn’t so much lacking inperformance, but from the dyno graph (p89)you can see there’s plenty of room forimprovement higher up the rev range.

Production of the E39 M5 didn’t startproperly until late 1998. That essentiallymeans that tuning specialists have had thebest part of 14 years to find the optimummethod of extracting more top-end powerfrom the S62. Countless different naturallyaspirated and force induced setups have

been trialled and released, and all have hadto adhere to the tight space restrictionsunder the E39’s bonnet. This in turn hasbrought with it flaws in many of thesolutions that have come to the market.Raise the bonnet and remove the frontbumper from the 5 Series, and you’ll noticethat there’s very little in the way ofstructural support so if you start cutting intoor removing sections to fit components,integral strength is very quicklycompromised. Finding extra power safely onan E39 M5 then, is perhaps more challengingthan on other models.

Unlike a number of superchargerkits for the E39 M5, Evolve’smounts the ’charger up top

behind the nearside headlight

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86 PERFORMANCE BMW

Evolve’s approach to tuning is one thatwe’ve always respected and appreciated.Where many companies seek all-outperformance and top-end, attention-grabbingpower figures, Evolve usually focuses itsattention on how the power is achieved anddelivered. It’s an ethos that reminds us ofone of those motivational posters: ‘It’s notthe destination itself but how you get therethat’s important’. It’s this line of thinking thatEvolve’s always taken with its highly-regarded remaps and ECU tuning, and it’sthis same direction it’s taken with its latestoffering for the E39. This Stage 2supercharger kit has been developed tosignificantly enhance the S62’s performancein all the right places. Great care was taken,though, not to lose the qualities that makethe third generation M5 so highly esteemed.

The setup revolves around the Rotrex C38-91 ’charger. It’s the latest and highest-speccentrifugal unit in the Rotrex line-up, and assuch is used by Porsche tuning house RUF,and supercar manufacturer Koenigsegg. It’ssuitable for engines ranging from 3.0-litres to6.0-litres and possesses three key qualitiesthat make it perfect for the M5.

The first is its superb efficiency. Putsimply, it delivers excellent boost at lowsupercharger speeds and therefore at lowengine speeds. Higher boost is obviouslyproduced as engine speeds increase throughthe rev range, but it’s at low speeds that

many other ’chargers are less effective.The second big positive with the Rotrex

item is that it’s significantly quieter thenothers on the market. While some love aloud, mechanical whine, a supercharger’stones should never dominate an engine’svocals and personality, especially when thatengine is a burbly S62 V8.

And finally, the C38-91 is also impressivelycompact. It has no right to pack the punch itdoes being so small. But its size is key toEvolve’s kit. As previously mentioned, spacecomes at a premium in an E39’s engine bay.In fact, a number of supercharger kits for thisparticular car position the ’charger itself lowdown, virtually out of sight. Doing so, though,makes it difficult to get goood belt wrap andclearance can even be a problem. However,Evolve’s kit sees the Rotrex unit sittingsnuggly behind the nearside headlight, solvingthese complications. Also, from a purelycosmetic perspective, it looks so much moreimpressive when the bonnet is raised.

Aesthetically you may have noticedsomething interesting about the carbon fibreintake elbow. Ordinarily, carbon fibre partsare lacquered, highly polished and thereforepleasing to the eye. What you rarely see ishow coarse and rough the opposite side is.Adopting the function-over-form policy,Evolve has reversed its intake elbows. Thatmeans the ultra-smooth polished surface ison the inside as this offers a lot less

resistance and therefore maximises airflow.Unlike the Stage 1 kit that Evolve lists for

the E39, this Stage 2 setup is intercooled. Ifyou ‘like’ Evolve’s Facebook page, you’llhave seen that countless hours ofdevelopment have gone into determining themost efficient setup. Twin intercoolers wereeven trialled for a period, but a single air-to-air unit was found to be particularlyeffective. Evolve has mounted this bespokeintercooler behind the offside front wing,where it’s fed ample cold air via the frontbumper’s left-hand air vent. Obviously, thearch liner requires a bit of modifying but it’sa super-tidy install.

And this minimal amount of intrusionmakes the kit even more appealing in ourbook. It’s a direct bolt-on setup. Aside fromthe arch liner adjustment, the only othermodification is the removal of a smallsection of rubber cowling for clearancepurposes. There’s no butchery required hereand the setup is completely reversible.

There are three versions of the setupavailable, basically differentiated by pulleysize and resultant boost pressure. The 6psisetup produces 580bhp while the 8psiversion is good for 600bhp. There is even a9psi option, but this will only be fitted toS62s running steel liners. The car we’retesting today is fitted with the 6psiarrangement. A 580bhp E39 M5? Thatsounds like plenty…

SOLUTIONEVOLVE AUTOMOTIVE’S

Evolve free-flowing headers arerecommended but not included

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JANUARY 2013 87

The Rotrex C38-91supercharger is usedbecause it’s efficient,

quiet and compact

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88 PERFORMANCE BMW

Before stepping into the supercharged M5,we’ve been trying to work out exactly whatwe’re expecting from it. As you can see fromthe dyno charts the E39’s ultimateperformance is delivered below 5000rpm –after that power increase tails offsignificantly up to 7000rpm. So first andforemost, we’re hoping for strongeracceleration right up to the redline.

That said, the C38-91’s design means itdelivers boost very early, making hugetorque available right from the off.Characteristically, the Rotrex unit thenspreads the power throughout the entirerev range. It’s more this aspect, coupledwith Evolve’s attention-to-detail when itcomes to power delivery that excites us,and here’s why…

While the E39 M5 is unmistakably fast,and its S62B50 undeniably brilliant, itsperformance is delivered with greatcomposure. What we mean by that is incomparison to say the S65B40 V8 in the E9xM3, or the S63B44 V8 in the F10 M5, theE39’s V8 feels less urgent. The needle movessteadily around the rev counter, it doesn’t

fly around and you wait patiently to changegear. Granted both of those other modelsare significantly newer cars, and the latterbenefits from BMW’s TwinPower Turbotechnology. But even though the E39 isn’tmuch slower on paper (only 0.5s slower to62mph than the E92 in fact), it doesn’t thrillyou in the same way. It’s not better orworse. It’s just a different drivingexperience. With Rotrex’s progressivesupercharger strapped on, though, and withthe smooth power delivery that Evolve’sECU tuning always gives, we wondered howthe driving characteristics would change.Time to find out…

Nestling into the driver’s seat, the firstthing we notice is that there are nounnecessary gauges and dials present. Itfeels positively stock in here and we like it.We turn the key, the V8 snarls into life andwe’re straightaway reminded that the S62 iswearing a pair of Evolve’s free-flowingheaders. It’s a delectable noise. “This is thequieter of our exhaust systems,” Imran fromEvolve smiles as he navigates us off theindustrial estate and points us in the

direction of the closest country lanes. The short drive across town along with a

little light traffic means there’s ample time forthe car to warm up. What we’re surprisedabout is how original the car feels, aside fromthe fruity exhaust system that is. There’s nolurching despite being on and off the throttle;it’s all very sedate. A VW Touareg peels off tothe right from in front of us and we’re leftfacing a pair of national speed limit signs.Time to squeeze the throttle…

Wow, this feels strong, but it doesn’t reallyfeel supercharged! The E39’s pulling andaccelerating much harder, but it almost feelsnaturally aspirated. The rush of air from theTIAL blow-off valve during each gear changereminds you that’s not the case, but we’re alittle perplexed. It’s almost like you’redriving a stock M5, but someone’s pressedthe fast forward button and it’s performingat x1.5 speed!

Okay, let’s be a little more objective aboutthis. We decide to try a number of second andthird gear pulls, so shift early to drop the revneedle nice and low. It’s the E39’s torque that’salways been its strong point, so does Evolve’s

ON THE ROAD

On the road, theE39 is blisteringlyfast, but strangely

almost feelsnaturally aspirated

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JANUARY 2013 89

kit affect this? Pressing the right-hand pedal,we’re expecting the S62 to feel a bit laboured.This is a big car, we’re three up and there’s aslight incline in front of us. We couldn’t bemore wrong. There’s absolutely no hesitationfrom the V8 and the unbelievable supply oftorque in its locker room is instantly unveiled.

We’re in third gear and the setup has justmade mincemeat of the early few thousandrpm, but we keep our toe in. The powerdelivery is silky smooth. The needle movesround the clock with pace, but at nomoment on its way to 7000rpm has therebeen a notable change in its speed as thesystem ‘comes in on boost’. It’s been ‘onboost’ from the moment we thoughaboutputting the pedal down!

Interestingly, there’s been no dip inacceleration after 5000rpm either. Instead,the E39 continues to pull strongly and at nopoint, at any rev or in any gear, has itindicated that it might let off. This car isblisteringly fast and the two characteristicswe wondered about and mentioned earlierhave both been addressed. The M5 hasbecome a lot more urgent in its power

delivery throughout the rev range, while itstop-end tail-off no longer exists.

The longer we spend behind the wheel ofthis car, though, the more we start toappreciate something else about it: it stillfeels like an E39 M5. This is not so much atransformation in performance, it’s aprogression. If you love how your E39drives, you will love this setup from Evolve.It doesn’t lose any of the M car’s personalityor drivability, even when making your waythrough town or sitting in traffic. It’seffortless and beautifully comfortable. But interms of acceleration, it does everythingbetter. It pulls significantly harder, but isn’taggressive. With the Stage 2 kit in place,your E39 will be in true supercar territory interms of outright pace and performance.Bearing in mind we’ve been driving the580bhp version and more powerful setupsare also available, we’re very impressed…

Evolve’s Stage 2 Supercharger Kit is a directbolt-on setup for the E39 M5. It’s intercooledand comes complete with injectors, crank

pulley, TIAL 50mm blow-off valve, bespokeintake and all the ancillaries required for analmost completely reversible installation.The kit is controlled by an Evolve AlphaNECU program.

Three different versions are available: 6psi(580bhp); 8psi (600bhp); and 9psi (610bhp+).Evolve recommends changing the rodbearings and strengthening the differentialmounting when fitting any of its kits, but willonly fit the highest power 9psi setup to anE39 with steel liners for reliability reasons. A full health check of your M5 will always beundertaken though before beginning asupercharger conversion.

Including VAT, Evolve’s Stage 2conversion retails at £9000, but to celebratethe launch of the new kit, free fitment iscurrently being offered at the specialist’sLuton-based headquarters l

CONTACT :Evolve Automotive

Web: www.evolveautomotive.comTel: 0871 231 1001

Where power increases start to level off from 5k on a standardM5, the supercharged car carries on up to 7k. The Rotrex’s

excellent boost even at low engine speeds can also be seen

APPLICATIONS AND PRICE

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