Building a McLaren P1 in One Week — The Challenge of a Lifetime
What a week it was. When we kicked off this project, we set out to do something that honestly bordered on impossible — take a McLaren P1, a hypercar that takes the factory roughly 800 hours and over 100 people to assemble, and bring it to life in just one week with the Car Council and Tavarish in Denver… all in time for SEMA.
This wasn’t just a project — it was a test of skill, creativity, teamwork, and endurance.
Day One — The Calm Before the Storm
Day one was all about getting our bearings. Parts were still in transit, so we assembled what we could and mapped out a plan of attack. It was the start of a long, chaotic, and unforgettable week.
Day Two — Making It Work
By day two, the improvisation began. Aftermarket parts needed to fit OEM McLaren components — not exactly plug-and-play. Freddie had loaner parts from his own P1 shipped from Florida almost every day, while we scavenged compatible pieces from a pile of used parts and even a donor 12C on the next rack over.
It was controlled chaos — wrenches flying, coffee flowing, and determination running high.
Day Three — Reality Sets In
Halfway through the week, we started to realize just how massive this challenge was. The to-do list still looked like day one. Intercooler lines didn’t line up, fittings didn’t fit, suspension components needed modification — and yet, nobody slowed down.
Everyone stayed late, knocking out lines, assembling doors, building out the dash. It was a race against the clock, and the team refused to quit.
Day Four — The Heart of the Beast
This was the turning point. The factory builds these cars with an army; we had a handful of guys and one short week. Every nut, bolt, and wire required detective work. Parts were still arriving daily.
Then, late that night, it happened — the P1 got its heart.
The M838TQ engine we built over a year ago at Cannonball finally slid between the frame rails after sourcing one last missing transmission bolt from the donor car. In that moment, the whole project came alive — and honestly, so did we.
Day Five — A New P1 is Born
By day five, it finally started to look like a P1 again. The lines were run, the ground straps completed, and the rear wheel wells installed. Kevin joined us to get the modules talking to each other, and after some fine-tuning, we were able to put power to the car for the first time.
In that moment, a brand-new, zero-mile McLaren P1 was born. The entire shop erupted in celebration — we even sang “Happy Birthday.”
After a week of late nights, long hours, and endless problem-solving, seeing that car come to life was nothing short of incredible.
Did We Make It?
Did we hit the one-week goal? Not exactly.
Did we fail? Not even close.
This 1-of-1 car deserves perfection, and we’ll take the extra time it needs to do it right. What we accomplished in five days was nothing short of extraordinary. We learned a ton, and we’ll only be better for it. This wasn’t just about building a car — it was about teamwork, creativity, and pushing the limits of what’s possible.
The Cannonball Way
We couldn’t be prouder of the crew Steve assembled, our Cannonball team, Freddy, Kevin, the Car Council guys, and everyone who followed along all week. You saw firsthand how this P1 tested us in every way imaginable, but that’s what Cannonball Garage is all about: taking on the challenges others won’t, doing it the right way, and having a little fun in the chaos.
UPDATE: We are back ….
Day Six — The Pressure
SEMA is rapidly approaching. We are back at it. The next two days will determine if we getr this American made P1 to the show on time.
This is the start of the final push. We have a skeleton crew working on what we can get done. Do we make it to SEMA? watch the day 6 update and find out!
Day Seven — The Finish Line
We had a BIG day on day 6. We are still feeling the glow-up from all we accomplished. We pressurized the suspension system to check its operation and it passed with flying colors.
Arne drove the over 1000 miles from Chicago to deliver us our McLaren factory hydraulic bleed machine.
We have a lot of work ahead of us. The coolant lines still need to be finalized. Do we still need more parts? We need to sort out wiring harnesses, the SKUG, and a whole lot more. Day 7 and we can see the finish line in the distance.
Day Eight— Buttoning It Up
We have a roller!!! We are buttoning this project up and getting it on a transport to SEMA! We cannot help but be amazed at the effort put forth by the entire to team to reach our goal. Stay tuned for an update from the floor of SEMA!
The American P1 — SEMA
The McLaren P1 #376 just rolled onto the show floor and it is absolutely breathtaking.
From a gutted shell and a literal shipping container of parts… to this. Every wire, every carbon panel, every custom billet piece, every sleepless night in the shop; it all led to this exact moment.
We’re standing here looking at a car that most said would never be impossible to finish in time, and all we feel is pure electricity running through the team. This isn’t just a build. This is the result of obsession, precision, and refusing to accept anything less than perfection.
To the owner who trusted us with his unicorn: thank you. To Ivan our CSO lead and Cannonball Garage technician who took the lead on this project: you’re the reason it’s here.
Come see #376 in person. Touch it. Feel what happens when a vision refuses to stay on paper.
We’ll be here all week. Stop by and let’s talk about what’s next for your build.
The finish line was never the end… it’s just fuel for the next one. 🔥