Each and every McLaren F1 was born special yet some are more special than the others, despite the company building just 106 examples, with just 64 of them being road-legal.

Chassis #018 is perhaps the rarest specimen of a road-legal F1. That’s because it features a high-downforce kit and LM-spec engine, making it one of only two LM-spec examples in existence.

RM Auctions is now going to offer the world’s best example of a road-legal McLaren F1 in its Monterey event on August 15. If there’s a time for top-tier collectors to go nuts during an auction, this is probably it.

Also Read:The Rarest Of The McLaren F1s Is As Magnificent As You Think

This particular F1 was originally finished in Midnight Blue over a black interior, but when it changed hands for the first time, its owner sent it back to Surrey, commissioning the LM-spec upgrades.

The engine was upgraded to the unrestricted GTR specification, meaning it now makes 680 HP and revs 1,000 rpm higher than the standard BMW-sourced V12 masterpiece. Along with the more powerful engine, this F1 features two additional radiators, a transmission cooler and a modified exhaust.

It also wears race-spec dampers and springs (which are set to their softest setting for road use) as well as a set of beautiful 18-inch GTR wheels. The bodywork features a deeper front splitter, tasty louvers over the wider front fenders and an impressive fixed rear wing; McLaren estimates its first-ever supercar now offers more downforce than the Le Mans-winning 1995 GTR race car!

The exterior was refinished in the current platinum grey color, while the interior was re-trimmed in cream leather, beige and brown Alcantara and got cream carpets and a 14-inch steering wheel. Even if you’re left untouched by the factory LM upgrades, though (which we doubt…), you have to admit that this is one superb way to an F1.

Despite the obvious race-derived parts, chassis #018 retains the road car’s interior, complete with an upgraded air-conditioning system and even a radio, allowing it to be driven with ease on public roads. The odometer currently shows 21,500km (13,352 miles).

Back in 2007, McLaren’s F1 service program manager Harold Dermott wrote in a letter to the current owner: “F1/018 is one of my favorite F1s and one of the most heavily developed cars that we have ever built” – a testament to the chassis #018’s quality.