The company also tweaks the body and fits a set of forged wheels.

As a roadgoing version of the McLaren 570S GT4 racecar, the McLaren 620R is already a hardcore, limited-run performance car. The company is only making 225 of them at a price of $299,000 each. Now, Novitec gets ahold of it to tune the model to be even sharper and more powerful.

Novitec's 620R pushes the 3.8-liter twin-turbo V8 to 701 horsepower (523 kilowatts) and 524 pound-feet (710 Newton-meters) of torque. In comparison, the mean McLaren's stock output is 611 hp (456 kW) and 457 lb-ft (620 Nm) of torque.

Gallery: Novitec McLaren 620R

Novitec estimates its version of the 620R can hit 62 miles per hour (100 kilometers per hour) in a very quick 2.8 seconds and achieve a top speed of 204 mph (328 kph). This is a tenth of a second quicker to 62 mph and 4 mph (6 kph) faster than the stock version of the supercar.

To achieve these improvements, Novitec has plug-and-play modules that tweak the mappings for the engine control unit. This setup allows the driver to return to the stock tune at the touch of a button. In addition to the extra power, Novitec claims that the throttle response improves with this upgrade.

The tuner also fits a new exhaust that it offers in stainless steel or the lightweight Inconel alloy. There are lighter catalytic converters, too.

A smaller adjustment is that Novitec fits the suspension with different springs that lower the ride height by 0.98 inches (25 millimeters). There are also a set of forged wheels with skinny spokes that measure 20 inches in front and 21 inches at the back. Customers can order them in 72 colors and pick between a brushed or polished finish.

Novitec makes some tiny design tweaks to the 620R, too. The company offers bare carbon fiber pieces for the hood scoops, side sills, mirror caps, and rear fascia. Inside, the business can cover the racing seats in leather or Alcantara in the buyer's choice of color.