Well-known Johannesburg tuner Rob Green Motorsport (RG Motorsport to those who move in tyre-smoking circles) is marketing a new conversion: a mega BMW M3 with enough power to make the earth spin faster - or slower, depending on which direction the car's facing.
Strapping a supercharger to the four-litre V8 engine, with a performance exhaust and a couple of other power-enhancing tricks thrown in for good measure, has boosted output from a standard 309kW to a fearsome 504kW, with torque up from 400Nm to 634Nm.
These are figures to make any red-blooded petrolhead drop his braai tongs and maybe even his beer as well.
And, of course, make any red-blooded motoring publication such as ours want to grab their testing equipment, strap it to the car and see just how much steak there is behind the sizzle.
Which is precisely what we did and we headed off to the Gerotek test centre near Pretoria to see what figures our Racelogic Vbox would come up with.
But first we took a peek under the bonnet to see the source of the volcano and found a very neat and professional installation with a brushed stainless-steel, aluminium and carbon-fibre intake system, all garnished with red and blue couplers. It's a bewitching marriage of art and engineering that's guaranteed to conjure a crowd of onlookers whenever you leave the bonnet open in the racing pits.
But enough eye candy, it's time to fire up and let the games begin.
The first impression is a good one as the performance exhaust system liberates an idling gurgle a good deal nastier than that of the standard M3.
There's serious poke to go with it and our first hint of what's really going on here is when we drive the car around town and discover that relatively innocuous throttle inputs get the traction control light flickering. The throttle is hair-trigger sensitive and has almost no play - it feels more like an on/off-switch.
That aside, it's a civilised car to drive through the suburbs with no lumpy idling or super-stiff clutch (RG didn't fiddle with any of that) and, were it not for that growl (and the occasional flickering light) you could almost imagine you're driving a regular M3.
Until the first open road presents itself and you squeeze the trigger. Aural and visceral pandemonium breaks loose as the boosted Beemer shoots forward like an enraged T-Rex.
The roar gets ever more red-blooded as the revs rise and by the 8000rpm redline it's a full-on vocal assault - this is some serious ear candy. And the car feels fast to go with it: seriously, wickedly fast in a way that grows phantom horns on your head and a very real grin on your face.
But would the rear-wheel drive Beemer have enough traction to dislodge the less powerful but all-wheel drive Porsche 911 Turbo from its throne as the quickest car we've ever tested? No, not quite.
Getting the power down without lurid wheelspin is a challenge in this M3 whereas the Porsche just grips and goes. After a couple of practice runs to perfect our launch technique and minimise the tyre screeching, the Rob Green M3 shoots to 100km/h in a best time of 4.2sec and does the quarter-mile in 12.2, in each case an improvement of about 1.5sec over a regular M3.
Very quick indeed, making it the equal second quickest car (with the Mercedes SLS Gullwing) we've yet tested, and slower only than the 368kW Porsche 911 Turbo which hit 100km/h in 3.5sec and did the quarter in 11.4. In overtaking acceleration Rob's ride does the business too by lopping two seconds off a standard M3's time in fourth gear from 60-120km/h.
In a sane world such relatively minor-sounding improvements would probably make it difficult to justify the conversion's R188 500 pricetag but the blokes who move in these circles are not your regular mortals.
They're on a go-faster obsession with not blood but octane-boosted petrol running through their veins, who would probably sell their own grandmothers to extract an extra two seconds.
If you're one of those click here. - INL Motoring