The McLaren Senna Is What Happens When You Build a Race Car Without Rules

The performance and tech McLaren has built into the Senna make it more GTE race car than road car.

image
McLaren

In order to truly synthesize McLaren's latest high-tech, high-downforce hypercar, we decided to send someone who'd be able to both understand the engineering and get the best out of the car. IndyCar driver JR Hildebrand was the man for the job. - Ed.

The modern breed of super-high-performance road cars can be so excessive that it’s difficult to really understand where they belong. Are they road cars with extreme track-inspired capability, or track cars designed for the road? Or are they made for the Texas Mile? Or for pulling up to the Aria in Vegas after hauling ass from LA with your mistress? Or for being the king of Cars and Coffee with a killer Insta feed?

Advertisement - Continue Reading Below

There’s really no right or wrong answer here–as can be seen by the growing market for any and all of the above–but for those of us who really care about the drive itself there’s serious risk in the answer being ambiguous. In many instances, they are neither road cars nor track cars and don’t feel particularly at home in either environment.

The McLaren Senna requires no such interpretation. To call it a road car would be wrong, to call it a track car would even be a disservice; it is unapologetically a full-blooded racecar that professional drivers and teams would lust after, and it just happens to be street-legal enough to get you to and from the track.

image
McLaren

When the Senna first appeared on our social feeds it was scrutinized for some of its angles and posture while sitting still in a garage. If you could ask it what it thinks of those opinions you might instead call it the Honey Badger. Its design has a purity of purpose much deeper than its appearance to the casual scroller’s eye. Also, it didn’t ask what you thought.

Advertisement - Continue Reading Below

The rear quarters are high to most effectively fit the high temp radiators while most efficiently directing air around the two-piece carbon fiber Monocage III cockpit to the back of the car. Hidden within each front fender are dual-flap wings (real wings, resembling those on the 2018 IndyCar), while the cutouts, vanes, and various structures around them divert, extract, or direct air for cleaner rearward flow. The front overhang is substantially more prominent than even that of the P1, all to maximize the ground effect from air traveling under the car to the tremendous double diffuser.

image
McLaren
Advertisement - Continue Reading Below
Advertisement - Continue Reading Below

There were some compromises to meet to street-legal homologation standards, sure–every edge on the surface of the car must be at least 3mm thick and rounded, making it a little less crisp than it might be otherwise, for example, and it does have suspension settings for non-track use–but the extraordinary commitment to this purebred philosophy is evident wherever you look, without exception.

Prior to getting behind the wheel I found myself putting the Senna’s performance measurables through my mental computer in comparison to other road cars, but frankly wasn’t sure what to make of it. 1,200kg dry weight, 800PS of power, 800Nm of torque, 800kg of downforce at 250kph. Ok, first the units are all wrong – 2,640lbs, 789bhp, 590lbft of torque, and 1,760lbs of downforce at 155mph – but even with the conversion done, what is there exactly to compare all that against? There are cars that light or that powerful or maybe both, but all the downforce, and all the intangible, immeasurable factors that go into how a car drives and feels?

image
The rear wing that you could eat dinner off of.
McLaren
Advertisement - Continue Reading Below

After a handful of familiarization laps around the Silverstone International Circuit in the highly capable 720S, I felt like physics had been altered getting into the Senna. First time into Stowe as the Pirelli Trofeo tires were still coming up to temp it became instantly clear that my frame of reference needed to be entirely reconfigured.

The car is raw, but with enough refinement and grip to be exceptionally confidence inspiring. You get all the visceral feedback through the machine that you’d expect from one with maximum performance in mind–sensitivity to load through the steering wheel, the sharp bite of rear grip through the seat, the crisp, intense sound and vibration of rising RPM at your back–all with enough notice of the car’s limits to push it over the edge and back without being on the knife’s edge. Within a lap or two I was driving this car more in the style I’d drive an IndyCar than how I was driving the 720S. It asked to be driven hard. After my first stint of several laps I got out in shock from having to rethink the car and what I was doing with it–this is an excellent high downforce racecar. Period.

image
McLaren
Advertisement - Continue Reading Below
Advertisement - Continue Reading Below

For reference, the dry minimum weight of 2018 IMSA GTLM cars is 2,750, 100lbs more than the Senna weighs. They are limited to the neighborhood of 525hp, 200 horsepower less. Downforce? I was quoted almost the exact same number as the Senna’s for their maximum possible trim level at any track.

And the Senna has active aero front and rear. And active hydraulic suspension...

image
The air brake at full attack.
McLaren

Gathering my thoughts I wondered, Am I even getting everything out of it? The first mental shift was treating it like a racecar instead of a street car–its statistical comparison to a GTE or GTLM car clearly warrants it. The second was realizing there’s even more there. It weighs less, has 200 more hp, and the same downforce… but the active aero and McLaren’s hydraulic K-damper connected suspension take it to a whole new level. The DRS that removes drag in a straight line is one thing, the massive airbrake created by the rear wing under braking is another–these alone would immediately be the most impactful tuning devices for a professional race team if allowed–but what makes this car truly special is the integration of the active aero and K-damper suspension throughout all phases of braking and cornering.

I spent an hour or so between my sessions quizzing the McLaren engineers about how it all actually worked–I was only going to get a few final laps to make discoveries on my own–and only then did I come to grips with the true mightiness of the car. Does the active aero adapt to how the car is being loaded, or is it more simply programmed for “braking,” “cornering,” and “straightaways”? Does it work with the other systems on the car, or is it more of a closed loop that functions based on its own parameters? What I really wanted to know was just how integrated the whole system of functions really is.

image
Hildebrand trying to get the McLaren guys to give him all the secrets held within the car.
McLaren
Advertisement - Continue Reading Below

The answer? The entire system of vehicle dynamics functions including the active aero and connected hydraulic damping is tied together and tuned for handling.

Normally when you trail brake into a high-speed corner in a high-downforce car you know that you risk pinning the car’s nose and getting increasingly unstable the deeper you try to go. As you brake, not only does the weight of the car transfer forward, but the aero-balance does as well due to the car’s change in pitch. High-downforce cars can be extremely sensitive to this effect, normally requiring quite a lot of attention be paid to how the car is transitioning through these cornering phases by the driver.

image
McLaren
Advertisement - Continue Reading Below
Advertisement - Continue Reading Below

If you do go too deep, managing the instability is also extremely delicate because you’re not only dealing with tires that can only handle a certain amount of slip angle, but the grip of the vehicle as an aerodynamic device that doesn’t like even the slightest amount of yaw. These are basic truths of a car with unchanging corner spring rates, damping curves, roll rates, and downforce distribution. I went back out with an intent to test the car in these situations and a recalibrated set of expectations to find that stability and grip was still there far beyond normal limits. Suddenly there became a whole new area of performance to chase.

image
Hildebrand belting in for a final run in the car.
McLaren

It was most apparent to me in high speed corners like Abbey and Stowe where this exact situation played itself out. While I’d normally have to plan my braking to diligently manage the pitch of the car into the corner, I was able to condense that entire phase of braking and cornering while carrying it further into the turns. The front wing was reducing angle and bleeding front downforce off the deeper I went then adding it back once the car was settled, the dynamic suspension controls were actively adjusting the car’s platform to secure its attitude.

Advertisement - Continue Reading Below
image
McLaren

Eventually you reach a limit of basic adhesion to the road, but the gains in both performance and confidence were undeniable. The same gains became evident in low-speed corners as more-than-once I thought for sure I’d overestimated a braking point and was able to neatly carve down to the apex all the same. In both situations I could feel the car just begin to do what I would normally expect at precisely the moment I’d expect it, but was able to break through that perceived limit in a whole new way. It also struck me how seamlessly it did these things–the dynamic systems of the car were affording me more room to play without noticeably cutting in and impeding my driving experience unlike many of the traction and stability aids out in the world. The process I was going through in exploring what the car could really do blew my mind. It was capable in ways that modern racecars could only wish to be.

Advertisement - Continue Reading Below
Advertisement - Continue Reading Below
image
McLaren

There’s no misunderstanding the McLaren Senna. It is not a road car. It’s not for the Texas Mile or hauling ass from LA to Vegas; for Cars and Coffee or Instagram. It’s not an evolution of the P1 nor is it the big brother of the 720S. It is the beginning of something new, of something we’re seeing a fresh glimpse of in this particular car – of a breed of hyper-focused hypercar built for an excessive experience rather than just excessive performance, free of anyone’s rules and regulations.

In the Senna, McLaren is showing that it sees the way forward and has gotten the jump off the line. For that, and the incredible experience the car delivers, I’m sure the man himself would be very proud.

Advertisement - Continue Reading Below

image
McLaren

Advertisement - Continue Reading Below
More From First Drives
https://steroid-pharm.com

www.gefest-sv.kiev.ua/

www.dopingman.com.ua/inekczionnyie-steroidyi/tren-e-h.html