The suspension was another major departure.
At the front, we used independent double-wishbone suspension.
Instead of both front wheels being rigidly connected to the same axle, each wheel could move independently.
The wheel was controlled by two roughly parallel suspension arms…upper and lower wishbones…which allowed us to control its movement much more precisely.
That mattered at Le Mans.
The circuit wasn't a perfectly smooth modern racetrack.
It was public roads with uneven surfaces, bumps, changes in elevation and corners taken at speeds that really had no business being possible on those roads.
We wanted the tyres to remain in contact with the surface for as much of the time as possible.
At the rear, we went with a solid live axle.
It wasn't as sophisticated, but it was robust.
And for an endurance car, robustness had value.
But the real magic was in the geometry.
We didn't just bolt the suspension together and hope for the best.
We mathematically experimented with it.
Again.
And again.
And again.
We tested different camber angles.
Different caster angles.
Different suspension-arm positions.
Different amounts of camber gain.
Camber was the angle of the wheel relative to vertical when viewed from the front.
A small amount of negative camber meant the top of the tyre leaned inward towards the car.
That could help keep the tyre's contact patch planted on the road during cornering.
Camber gain was what happened to that angle as the suspension moved.
We wanted it carefully controlled.
Too little, and the outside tyre could lose contact with the road when the car cornered hard.
Too much and we'd simply wear the tyres out while sacrificing straight-line stability.
Caster was different.
That was the angle of the steering axis when viewed from the side.
More caster could give the steering greater self-centring and improve stability, particularly at speed.
And at Le Mans, stability at speed was rather important.
We spent days testing different configurations.
Dozens of them.
Every change was documented.
Every test was recorded.
Every failure was written down.
We recorded component temperatures, loads, pressures, lap times, fuel consumption and anything else we could reasonably measure.
It sounds tedious.
It was tedious.
But it meant that when something broke, we had a much better chance of knowing why it broke.
And that allowed us to fix it.
The tyres were another nightmare.
We needed a manufacturer willing to actually work with us rather than simply sell us whatever racing tyre they already produced.
We needed something capable of dealing with high speeds, long periods of continuous running and repeated heating and cooling cycles.
Cold-start behaviour mattered.
Operating temperature mattered.
Pressure mattered.
The difference between a tyre that felt wonderful for ten minutes and one that remained predictable for several hours was enormous.
And then there was the aerodynamics.
That was where things got genuinely interesting.
Most racing cars of the period weren't exactly designed with sophisticated aerodynamic principles in mind.
We were.
We wanted to reduce drag wherever possible, but there was an important caveat.
We absolutely could not accidentally turn the car into an aeroplane.
Reducing drag was useful.
Generating lift was not.
So the body was shaped with a rounded nose, a smooth bonnet, a narrow cockpit and a tapered tail.
We tried to avoid abrupt steps, exposed components and unnecessary sharp transitions.
The underside was made as smooth as we could reasonably manage with the technology available to us.
It wasn't perfect.
We couldn't magically build a modern aerodynamic floor in 1925.
But every little improvement mattered.
Crosswinds, however, nearly killed the project.
Not literally.
They just nearly killed a driver.
Our early aerodynamic experiments produced cars that behaved rather badly whenever a strong gust hit them from the side.
Which was somewhat concerning when we were designing a car expected to travel at around 180 kilometres per hour.
This was why we had test drivers.
I wasn't putting Kitty in the prototype.
She wanted to drive it.
Obviously she wanted to drive it.
I told her no.
She argued.
I continued telling her no.
Eventually, we hired professional test drivers.
Which turned out to be an excellent decision.
One of them eventually suffered a catastrophic accident and was left paralysed from the neck down. Even though I would pay a pension for the rest of his life, it didn't change the fact of what happened.
The drivers sat one behind the other rather than side by side.
We needed two people because we didn't have computers or modern telemetry.
One drove and the other watched the instruments, recorded information, kept track of lap times and fuel consumption, and generally did the sort of work that a modern data system would eventually automate.
We added four-point harnesses.
Padded headrests.
Padded cockpit edges.
Fire-resistant materials.
Fire-resistant clothing.
And, importantly, we attached the harnesses directly to properly reinforced mounting points in the chassis.
The idea of putting seat belts into a racing car was not particularly popular.
People argued that drivers needed to be able to escape quickly.
People argued that being strapped into a car during a crash was dangerous.
Then we started actually crash-testing the cars.
Funny how quickly opinions changed.
After watching a dummy remain inside the cockpit instead of being launched through it, everyone became considerably more enthusiastic about seat belts.
We also installed fire-suppression systems around the engine and fuel systems, along with kill switches for the ignition.
The magneto ignition itself had another useful advantage: unlike a battery-dependent ignition system, it generated the electrical energy required for the spark itself. It was robust and well suited to a racing engine.
The cockpit ended up looking like a mechanical laboratory.
There was a tachometer for engine speed.
A speedometer. Oil-pressure and oil-temperature gauges. Coolant temperature. Fuel pressure. Fuel level. An ammeter. A clock. A trip odometer.
And a collection of other indicators that I was increasingly convinced existed primarily to make the dashboard look intimidating.
Hence why the navigator's job was just as important.
They recorded lap times.
Fuel consumption.
Oil temperature.
Coolant temperature.
Anything unusual.
Anything that changed.
Every run produced another page of notes.
Every page gave us another piece of information.
And every piece of information made the next version of the car a little better.
We didn't do much with the differential.
There simply wasn't that much we could realistically improve without turning the entire drivetrain into another enormous engineering project.
So we left it alone.
There were only so many battles we could fight at once.
Eventually, after months of development, testing, failures, redesigns, arguments and what I can only describe as industrial-scale amounts of money, we finally had the finished car.
Three litres.
Straight-six.
One hundred and fifty horsepower.
Roughly 950 kilograms race-ready.
A top speed somewhere around 180 kilometres per hour.
Though, honestly, it was much happier cruising around 135.
Four-wheel hydraulic brakes.
Independent front suspension.
Solid rear axle.
Dry-sump lubrication.
A reinforced steel chassis.
Proper harnesses.
Fire suppression.
Overbuilt cooling.
Carefully designed aerodynamics.
And enough instrumentation to make the cockpit look like the control room of a very small submarine.
It wasn't the fastest car on the track.
That wasn't really the point.
A Lorraine-Dietrich could still outrun us on the straight.
Whatever Bentley cooked up could probably do the same.
If all we cared about was top speed, we'd already lost.
But Le Mans wasn't one straight line.
It was twenty-four hours.
And our car didn't need to beat them once.
It needed to beat them again.
And again.
And again.
Every lap.
For hour after hour after hour.
That was the entire philosophy behind the car. We weren't building the fastest car in the world. We were building the car that could out average every other car over 24 hours. And we still had months to perfect it.
[Le Mans, France – 4:54 PM, 15th of June, 1925]
She came through the corner and onto the straight, the little silver car bouncing over the rough surface, its bodywork filthy now. It had been beautiful yesterday.
It looked almost ruined today.
There were black streaks along the sides. One of the lamps was cracked. The silver voice had disappeared beneath a film of dust and oil. The number 4 was barely visible on the side.
But the engine was still running.
That was all I cared about.
She crossed the line.
Six minutes left…
I let out a breath.
I hadn't realised I was holding it.
Someone beside me said something.
I didn't hear them.
I watched the end of the straight.
Then the car vanished around the corner.
And I waited.
That was the worst part.
Waiting.
There was nothing I could do.
I could not make the engine run better. I could not cool the brakes. I could not tighten a bolt or adjust a carburettor. I could not reach through the bodywork and put my hands around the machinery and simply make it hold together.
I could do nothing but watch my wife drive it.
Five minutes left…
I simply watched.
Four minutes left….
The sun was higher now.
I was exhausted. Everyone was exhausted. The men in the pits looked as though they had aged ten years in the last day.
And yet Kitty kept going.
Three minutes left….
I found myself thinking about the first time she had driven the car. How she had climbed into the cockpit with that ridiculous little smile of hers and asked me whether I was frightened. I'd told her no.
She had laughed because she knew I was lying. I had been terrified.
In truth I was terrified now.
Two minutes left…
The timing board still showed us first.
I stared at it.
The number seemed impossible.
Somehow…
…our car was still first.
One minute left...
The crowd was standing now.
I looked down the straight.
Nothing.
Nothing.
Nothing.
Then I heard it.
That engine.
I knew that sound better than I knew my own voice, and as I saw the car, my heart stopped.
She was coming.
The final lap.
I couldn't breathe.
The car disappeared.
I looked at the clock.
I looked at the track.
Then back at the clock.
How long could one lap possibly take?
I had designed the car to do it in minutes.
Those minutes suddenly seemed like hours.
I thought about all the things that could go wrong: A tyre, a valve, a bearing, a gearbox, a puncture, A single broken wire, a single loose fitting.
The engine could fail anywhere.
The car could leave the road.
Kitty could…
No.
I wouldn't think it.
I gripped the railing until my fingers hurt, and then, in the distance, I saw something silver.
The crowd erupted.
The sound hit me a moment before the car reached us.
She came down the straight…slowing to pull into the pit.
The engine was screaming.
The car was moving.
And then…
The timer hit zero. The 24 hours we're up
"La voilà! La voilà! Elle franchit la ligne! La numéro quatre est victorieuse ! Elle a gagné! Elle a gagné les vingt-quatre heures du Mans ! Quelle victoire extraordinaire !" cried the announcer. ("There she is! There she is! She crosses the finish line! Number Four is victorious! She has won! She has won the 24 Hours of Le Mans! What an extraordinary victory!")
Someone grabbed me from behind. Another man shouted something directly into my ear. The pit had erupted. Men were climbing over the wall. Someone was crying. Another was laughing. A third had thrown a hat into the air.
And I ran.
I don't remember climbing down from the grandstand.
I don't remember crossing the distance.
I remember only the car slowing.
I remember the brakes.
I remember the engine coughing as Kitty brought it to a stop.
I remember the door opening.
And then she was there.
My wife.
I marvelled at her bedraggled look as she fought for a moment to remove her helmet. Her face was black with soot and streaked with sweat. There was blood on one of her knuckles. I still to this day don't know where it came from.
She looked at me, and for a moment, neither of us said anything.
Then she smiled. Not the confident smile she wore before a race. Not the teasing smile she gave me when she knew she'd won an argument. This was different.
Small.
Almost disbelieving.
"We did it," she said, visibly trying to stifle her heavy breaths.
I tried to answer.
Nothing came out.
She laughed.
"We actually did it."
I put my arms around her. I didn't care who was watching. I didn't care that there were officials standing ten feet away. I didn't care that there were reporters already pushing toward us. I didn't care that there were cameras. I simply held her.
She wrapped her arms around me and buried her face against my shoulder. And then I felt her shaking. She was crying. Whether from exhaustion or happiness, I do not know. Probably both.
We had spent the last year being told what this would mean. What it would prove. What people would say. And suddenly none of it mattered. There was only Kitty.
My Kitty.
Standing in my arms.
Alive.
Safe.
And a winner of the 24 Hours of Le Mans.
I pinched her chin and pulled her face towards mine.
I kissed her as she raised slightly to reach me.
She laughed against my mouth and kissed me back.
Someone shouted.
A camera flashed. Then another. We didn't stop.
It wasn't passionate, nor was it chaste; it was simply a kiss.
For those few seconds, there was no racing team, no reputation, no press, and no argument about whether a woman ought to be driving a racing car.
There was simply a husband and his wife.
And she had just won Le Mans.
I would see the photograph the next morning.
I would see it before I saw the race results.
It would be everywhere.
Kitty with a helmet in one hand.
Me holding her.
Her other arm around my neck.
Both of us exhausted and laughing through tears.
The car behind us.
The mechanics around us.
And that crowd in the background.
Thousands of people standing.
Some cheering.
Some staring.
Some are simply trying to understand what they had just witnessed. The newspapers would have their say. They would call her extraordinary, reckless, brave, and a novelty. There would be men writing that she had been lucky. Men were writing that the car had won it for her. Men were writing that her husband had funded the whole thing and therefore the achievement belonged to him.
Others would say that she had made fools of every man who had laughed at her.
Some would insist that it was bad for women.
Others would insist that it proved women could compete with men after all.
They would argue about Kitty for weeks.
Perhaps months.
Perhaps years.
But I knew what none of them did.
She had done it not to prove a point nor because it was easy, but because it was what she wanted to do. I had seen her climb into that car yesterday morning. I had seen her climb out of it twenty-four hours later. I had watched every mile. Every corner. Every pit stop. Every moment when the engine sounded wrong. Every time she disappeared from view, I wondered whether she would come back.
And I knew that the photograph everyone would remember was not really about Le Mans.
It was about the moment when she came out of that car and came to me.
That was what I saw when I looked at it.
Not the woman who had made history.
Just Kitty.
My wife.
And the woman I had spent two years believing in.
The world would argue about what she had proved.
I never had to.
I already knew.
That photo, though, became more than the moment it captured; by the modern day, it's part of the cultural zeitgeist around racing. A book about women in racing – it was their. A lecture about the 1920s was one of the default photos shown to classes of students. A documentary about British motor history…it was part of the opening credits. It's one of those things you don't even plan…even people who had never heard of Catherine Sullivan recognised the photo.