Building a race car takes a lot of work. And we had more to do before our project was ready to enter its first time trial event.
As we detailed in the last two installments, fabricating a cage and gutting the interior were no trivial tasks.
Now we needed to reconfigure that interior for racing. All while adding as little weight as possible, since those extra pounds make cars slower and more expensive to campaign on track.
Now that our 350Z has a cage, we need to trim out the interior. Since we’re building this car for NASA Time Trial competition, we don’t need to retain the factory dashboard.
First on our list: What to do with the car’s dashboard? During this entire interior makeover, the original dash has sat on a shelf in the corner of our shop.
Should we even reinstall it? The benefits would be a finished appearance and reduced glare.
The cons, though? Dashboards add weight, can be flammable and limit access. Oh, one more: They’re tricky to mount around roll cages. If you ever go this route, expect to spend lots of time hacking chunks off with an air saw. In fact, unless it’s specifically required by a rule book, we’d say to just leave the factory dash out of a purpose-built race car.
Boom. Into the attic it went. Why not just chuck it? We figured if, for some reason, we needed to reinstall the dash, we’d know where to find it. Weight savings: 10 pounds.
Then we pulled the factory heater core out of the car for a 14-pound weight reduction. We kept that, too, in case it comes in handy down the road–perhaps for an endurance race where we’d need to defrost the windshield. Leaving the heater core in place during cage fabrication ensured that we could easily reinstall it.
We could toss the heater core, too, although we’ll save it for a rainy day.
Ditching our dash and heater core meant we could toss our dash bar, too. This contorted piece of tubular steel is a staple of any modern car. One of its jobs: to support the very parts that we just removed. Into the attic it went as well, shaving an additional 13 pounds from our car.
We ditched the factory dash bar to save weight.
We’d removed 37 pounds but created more work for ourselves in the process. Why? Because the car’s steering column wanted to mount to a dash bar that we no longer had–and the factory instrument cluster wanted to mount to the column. And then, to add more pieces to the puzzle, more gauges lived in the middle of the dash that we had just jettisoned.
We had to find a new solution, starting with the gauges. Even though the stock gauges still worked with the LS1 engine–thank you, LOJ Conversions wire harness–we wanted something more suitable for track use.
The heart of our new setup would be an AEM CD-7 Carbon Logging Digital Dash. Why spend $1725 on a digital dash? This is more than a dash, it’s a pro-level data-acquisition platform that we can then pair with AEM’s $380 vehicle dynamics module for lap times and accelerometer data.
Our new setup would center around AEM’s CD-7 Carbon Logging Digital Dash.
This setup will let us tweak the look and feel of our gauges on the fly, automatically prioritize alerts and alarms for anything conceivable, and provide performance insights that were only available to pro-level teams just a few years ago. It’s easy to install, too, only requiring power and a connection to our PCM.
Why’d we pick the AEM instead of another digital dash? We really, really liked its look and feel. AEM pitches it as the lightest, brightest dash on the market, and after experiencing it in another car, we were hooked. More importantly, it communicates over CAN bus, so it works automatically with hundreds of third-party devices, from our GM PCM to a wide range of aftermarket ECUs to additional sensors we’ll add in the future. AEM’s AEMdata analysis software is powerful, too, and we should be able to quickly gain insights from it while sitting in the paddock between sessions.
We also took this opportunity to ditch our 350Z’s stock air bag-equipped steering wheel. Instead, we chose a 330mm diameter Sparco racing wheel and 350Z-specific adapter from Summit Racing.
Our new 330mm Sparco wheel is better suited to our needs than our stock 350Z wheel.
The combination set us back $340, pricier than the off-brand wheels and adapters you’ll find on Amazon. Why not save some money and buy a cheaper wheel? Flex. Some people don’t mind a wheel that flops around like a limp noodle, but after making that mistake on our V6 Miata, we’ll never skimp in this department again.
We did save some cash, weight and complexity by skipping the quick-release hub, though. Chalk it up to dumb genetic luck: Our driver is skinny enough to easily squeeze into a race seat without removing the wheel.
Bonus points: Our tilt steering column still works.
We had a plan–ditch the stock dash and instruments–but now we needed to execute it. Fortunately, we planned ahead here. Thanks to some careful pre-cage measuring, we had the cage’s dash bar perfectly placed to accept the steering column. We didn’t need to build something from scratch.
Instead, we simply pulled the stock mounts from the factory dash bar with a plasma cutter. After some cleanup work with a grinder and some reshaping with a hammer, we were ready to reuse them on the cage’s dash bar.
Removing the original dash bar meant that we’d need a new way to secure the steering column. This bracket, swiped from the OEM dash bar, would provide the upper column mount.
First, though, we needed more room to work, and the windshield was in the way. Our local glass company, Independent Auto Glass of Ormond Beach, had the glass out in less than 15 minutes, giving us plenty of access to weld on the dash bar.
We worked slowly and methodically here, pulling the seat in and out to protect it from sparks as we tacked, tested, adjusted, measured and planned. Eventually we arrived at the perfect location for our steering column. Then we welded both its upper and lower mount to our new dash bar, with the latter mount extended by some angle iron to link everything together.
Mating that steering column bracket to our Kirk Racing cage was easy: Clean up the edges, bend it a bit to fit the smaller-diameter bar, and weld it in place.
The result was rock solid and added only about a pound to the car’s weight. Perfect. Note that we maintained the factory’s bolted-on connections, so down the road we can remove our column without cutting.
We used some angle iron to locate the driver-side lower column bracket. Now we could bolt the steering column back in place.
Look closely, and you’ll notice that we left the factory clockspring and control stalks on our steering column. Why? Because for the time being, we’re going to keep our car’s wiring harness intact and make it easy to reinstall the wipers should rain start falling. The easiest way to control a modern car’s wiper mechanism is via the factory switches, and the plastic stalk is light, reliable and free.
After mounting the steering column, we reinstalled the race seat and grabbed the AEM display. Then we started mocking up mounting options.
We wanted the display directly in our line of sight, not off to the side. We eventually arrived at a lucky conclusion: A simple bracket allowed us to mount the display to the steering column using the factory cluster holes.
We built a simple mount for our AEM display. First, we mocked together some thin aluminum square tubing. Then we welded the tubes together.
After some quality time welding extremely thin-walled aluminum tubing, we’d built that bracket: a strong, easily removable mount that weighs just 6 ounces.
Success! The result is strong and light.
After a day’s worth of work, we had a sturdy steering column with a beautiful dash perched on top. Our race car was complete.
Okay, just kidding. We’d crossed the big-ticket items off our list, but our interior still had a way to go–and a lot of weight to lose–before we could hit the track. We’ll continue that process in the next update.
Our cockpit is starting to come together. We still have some cleanup to do, but we’re nearly ready for the track.
Like what you're reading? We rely on your financial support. For as little as $3, you can support Grassroots Motorsports by becoming a Patron today.
View all comments on the GRM forums
You'll need to log in to post.
