G-Power boosts BMW 1M to 435hp

German tuner G-Power is not, it has to be said, a company you could ever consider shy.

Its previous triumphs include twin-supercharging the 5.0-litre V10 from the BMW M5 up to 900hp – and occasionally emphasising our original point by installing them in rather unnecessary places, such as beneath the bonnet of the BMW X6.

Now G-Power has been interfering with the BMW 1 Series M Coupé.

First Drive Review: BMW 1M Coupé (2011 onwards)

G-Power 635hp BMW M3 GTS

For better or worse, this hasn’t involved cramming in the V10 – even G-Power has some sense of restraint it seems (or at least a realistic grasp of a tape measure). Instead it’s focused its nefariousness upon the standard 3.0-litre straight-six, which by virtue of twin-turbos already produces 340hp.

Replacing some of the pipework with bespoke “flow-optimised” upgrades, improving the cooling system, reworking the ECU software and fitting a new titanium exhaust, G-Power has cranked this up to no less the 435hp.

That’s 95hp more than stock. Similarly torque is increased from 369lb ft to 435lb ft – which is not only mighty impressive, it’s actually 144lb ft more than the current BMW M3. The G-Power 1er also packs 15hp more than big brother.

The result is 0-62mph in 4.5 seconds, and a top speed of 186mph – besting 4.9 and a limited 155, respectively. Ought to be enough given the short wheelbase and the 1M Coupé’s cheeky handling.

Aiming to help you out on that front, G-Power also offers its own fully adjustable suspension package. And much bigger brakes – six piston calipers, braided brake lines, higher friction pads, plus the option of ceramic discs if you don’t think the steel items are going to cut it.

The ceramics also reduce unsprung mass by 50%. Perhaps offsetting that slightly, the car pictured here is also running “Silverstone Diamond” alloy wheels that are an eye-watering 20 inches in diameter.

Talking of weight savings, that special titanium exhaust is 20kg lighter than the standard item, and comes with a choice of carbonfibre or titanium tip finishes. Oh, and it has an electronically switchable valve to bypass the silencers, bringing noise up to what G-Power describes as “racing levels”.

Just to prove how serious it is, the company has even provided a price list.

The engine work – including the titanium exhaust – comes in at €10,238 (that’s around £8,000; the wheels and tyres are €4,475 (£3,500); the suspension mods €1,721 (£1,350). None of the pricing includes fitting.

You might want to take a seat now before you look at the braking upgrade, though, as the full ceramic package is €14,461 for the front and €11,778 for the rear. That’s €26,239 (£20,800) all in.

Fancy the whole lot and you’ll be looking at around £33,650 before anyone’s even picked up a socket wrench. Or very nearly the cost of the car all over again.

Even so, we bet you still want one… Easy on the orange detailing if you please.

777hp chocolate brown Lamborghini Aventador looks tasty

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First Drive Review: BMW 1M Coupé (2011 onwards)

G-Power 635hp BMW M3 GTS