The McLaren P1's engine is actually inspired from a one-off Nissan supercar
I think the phrase to describe McLaren Automotive's modern entourage of vehicles is 'ferociously clinical'. With their carbon tubs, the most functional of functional aero packages and looks that will have any architect frothing at the pencil case, the Sports and Super Series cars from McLaren have taken the supercar industry by storm. Ferrari and Lamborghini have been dealt some serious blows over the past few years and with the 720S stepping up the game even further (some say it is already P1 fast, without the electronics), it doesn't seem like the ladies and gentlemen at Woking are letting up anytime soon.
Possibly the key aspect to McLaren's recent success has been the use of its M838T engine which has been used in both 3.8-litre and 4.0-litre form (M840T). The twin turbocharging of these compact units has seen power outputs soar to 727bhp before electrical assistance in the P1. The least powerful McLaren on sale still produces 533bhp; not bad for an entry level model.
Taking the M838T back to its roots however uncovers an interesting story that begins with the unlikely perpetrators of Nissan and its Le Mans programme. In 1988, Nissan entered its R88C racer into the fray of Group C with a thunderous mid-mounted V8 known as the VRH30. The 3.0-litre twin turbocharged unit was bored out to 3.5-litres for the '89 season and sat in the R89C, being structurally integral to the car. In full Group C tune, the engine was made to output in the region of 950bhp.
After a brief hiatus from motorsport, Tom Walkinshaw Racing (of Jaguar fame) partnered up with Nissan and updated the engine to become the VRH35L used in the iconic R390 GT1 supercar. The powertrain was reduced from the manic days of Group C down to a more docile 640bhp.
The engine code name can be dissected to:
V = V engine configuration
R = Racing
H = The eighth letter of the alphabet = eight cylinders
Then came the resurgence of McLaren's road car division who - when coming up with a design for its first supercar since the F1 - had to pick an engine worthy of the job. The twin turbocharged nature (and therefore high tunability) of the Nissan power unit obviously attracted the engineers and the rights to the engine's design were purchased by McLaren, initially for research purposes.
McLaren then dissected the engine and began to produce its own powertrain for the MP4-12C supercar. And although the Nissan block was the design inspiration for McLaren's new powertrain, the only aspect that the engines seemingly ended up sharing was the bore size of 93mm.
Ricardo was commissioned to manufacture the engines and Tim Yates (the Project Director for the McLaren Automotive Programme at Ricardo) said at the time: "In terms of components, just about everything is bespoke in the engine. There are very few components that you would recognise from another application". The intake manifold, oil cooler filter module and the cam covers were changed to plastics instead of aluminium to meet the weight target governed by McLaren, along with virtually the entire entire block.
So it is only really the layout, bore and twin turbocharged nature of the engine that survived the McLaren-Ricardo development phase from the original R390 GT1 supercar. But still, it's a good one to have in your pocket when you're down the pub for the car quiz night.