My plan for this series was to break down the build of a Pikes Peak race car and make it nice and orderly. It’d start with buying a salvage donor car, designing a roll cage, then go through making carbon fiber parts and finish up with engine and performance upgrades before the race. Well, any plans of nice and orderly went straight out of the window this week and we’ve had one issue after another kicking us straight in the tender bits. Progress has been anything but orderly.
Welcome to the reality of race car builds, where the one thing that you can count on is that you can’t count on shit.
(Full Disclosure: This is a story about building a race car for the Broadmoor Pikes Peak Hill Climb. Some, if not all, of the companies involved have sponsored this build in some way, shape or form. Without their support this build would not be possible and therefore there would be no story. If you do not want to be exposed to these companies and think that somehow, in some way, sponsorship is bad, then please do not read this article… and give yourself 1,000 lashes for thinking impure thoughts about being unduly influence by your exposure to sponsors. Shame! Shame!
Also, I am bringing back the deal that I did for the 24 Hours of Nurburgring a few years ago where you can get your name/logo/personal life motto printed on our massive wing or splitter for the hillclimb itself. Head over to my site SalvageSupercar.com to sign up. (June 22 is the last day to sign up).
With the roll cage finished, everything had been progressing on pace. The car was shipped over to NRG Motorsports to start putting Humpty Dumpty back together again.
One of the primary tasks NRG had was reinstalling as many of the OE sensors and electronic bits and bobs as possible. That might seem counter productive for building a race car, but years of experience have taught me that actually the exact opposite is true.
Back in the heyday of motorsports, home built “Garagistas” ruled the sports car scene. It was easy enough for any Bill, Bob, or Joe to pull a street car off a dealers showroom floor, haul it home and with a bit of knowledge and elbow grease turn said street car into a race car capable of winning an SCCA Pro race. Kind of a “Buy on Saturday, win on Sunday, sell on Monday” scenario. But since the advent of modern in car electronics that is no longer possible, or at least much more difficult.
A few years back I drove for the factory Volvo Touring Car team in Pirelli World Challenge and documented the build of the Volvo C30s for Jalopnik (very similar to this series actually.)
One of the things I glossed over in those posts was the never-ending issues we had in dealing with the factory electronics. It was so difficult for the team—a factory level pro team—to deal with, that engineers from Volvo had to fly out from Sweden and physically sit in the race car, while I was doing laps, to debug all of the systems.
What makes it so difficult? Well modern cars are packed with an ever-increasing number of sensors, all attached to the ubiquitous CAN bus system. That’s your car’s internal computer network, a network and set of standards computers in the car use to talk to each other and get data.
Basically, the sensors in the car all talk to each other and each one has the ability to take information off the system and use that information to assist in controlling its function. For a simple example, the braking system takes wheel speed, steering angle and brake pressure data off the CAN bus and uses that information to calculate the amount of anti-lock braking needed in a given situation.
That’s a huge advancement in current day street cars, increasing the performance boundary for by orders of magnitude over their predecessors. This is a closed system, though, so if you remove any one piece of that system, any one of a number of different systems may not function as expected or worse, not function at all. Case in point.
With our Pikes Peak Z06 generally back together we decided to take it out to one of our local tracks Pikes Peak International Raceway (PPIR) for a quick systems shakedown. The goal was to see if any of the things we pulled off the Z06 would cause any issues with the car. Surprise, surprise. They did.
The first lap out I knew all was not well. At 70 mph the electric steering suddenly went dead. Then, going into the first hairpin I locked up both rear tires, which shouldn’t be possible with ABS brakes. We pulled the car into the garages and spent several hours using our factory scanner to see what fault codes were coming up. We hoped it would give us some indication as to what missing sensors the car deemed crucial.
Here’s what came up:
- C025E—(vacuum sensor signal is not plausible) Electronic Brake Control Module (EBCM)
- U0151—Lost Communication with Restraints Control (RCM) Module (Airbag control module)
- U0128—Lost Communication with Park Brake Control Module (PBCM)
- U042B—Invalid data received from chassis control module A
The first code C025E could have everything to do with our ABS problem but far less likely to have an effect on the steering problems.
Code U0151 we were expecting as the air bags were blown in the initial accident and rules for Pikes Peak prevent us from replacing them (not that we would). Oddly, we ran the car without airbags at the track before we stripped the car down and we had none of the issues that we were currently seeing. At least we could rule out the lack of an air bag as the source of all of our general issues.
The last code may have had something to do with removing the stock active suspension and replacing it with the JRZ motorsport coilovers. Active suspension is normally the Holy Grail of suspension systems. However, the stock stuff on the Z06 was not designed to work with the super sticky Pirelli slicks I’ll be running. Hence the switch to the JRZs.
The problem is that the stock suspension in the Z06 is electronically controlled and monitored. As I’ve mentioned, removing any of the electronics in a modern car is like playing in traffic. It isn’t if you’re going to get hit, it’s a matter of when.
In the Z06, damn near half the systems rely on information coming from the suspension. The ABS, the active rear differential, the steering and more. The only way to remove the OE suspension is to trick the car into thinking that the active dampers were still there. And in order to trick the Z06, you have to be smarter than it. Embarrassingly I am not, so I had to find someone who is.
This is how I met my new best friend, Max Darrah, over at Xineering. Max is smarter than me, but more importantly he is smarter than my Z06. He’s so smart he even came up with these nifty little sensors that trick the Z06 into thinking that the stock active dampers are still there. They send out all of the right information to keep the car as a whole happy.
Having a guy who knows and understands these systems, to help sort through these things, is absolutely crucial in trying to turn a modern street car into a race car. And that is how Max has become our go-to guy for all electronic questions. (I’m sure he regrets responding to my email a few weeks back.)
Oh and the ABS and steering problems? It turns out we simply lost a rear wheel speed sensor. Both the ABS and steering systems need wheel speed information supplied by that sensor. Why that didn’t trip a fault code we have no idea.
If that were the end of our problems we would be all smiles and knee deep in our testing program. However, it turns out those were, if not the least of our problems, just the start of them.
At the moment a majority of our issues are being caused simply due to the late start we got in getting this build underway. Had we started at the end of last season, say October, I would have only been a little bit concerned about being ready, as a proper race car development program takes at least a full year. However, as we didn’t get underway until March of this year, I’m more in absolute panic mode.
People are always asking me how much time it takes to build a race car. My answer? Every waking moment from when you start until the first race, plus a week.
The other issue that we have with this particular build is that the Z06 is a relatively new car, and has never really been raced—the GTE and GT3 Corvettes are pure race cars with very little to do with the street car. So there are relatively few motorsports parts available. Not only are we the guinea pigs for several performance part manufacturers, but a lot of the bits going on our car didn’t even exist a couple of months ago. Just one subcontractor being delayed on shipping parts means our whole show comes to a screeching halt.
Right now the list of things that are delaying the completion of this build (in no particular order)
- Subcontractor delay in machining mounting pins for our JRZ coil over race suspension
- Subcontractor delay in getting our upgraded parts for our fuel system
- Notified by subcontractor that delivery of our Alcon brake rotor hats and caliper mounts will not be possible by race week
We have managed to come up with solutions to all of those issues, or they’ve solved themselves. (Dampers are finished and are on their way to us, we can run different fuel if the parts don’t make it in time, and we will just run the stock OE Z06 braking system with upgraded Motul brake fluid.)
Solving those issues, however, only means we have moved on to new ones. The latest issue is a complete and utter failure of UPS to do the one thing that they exist to do: deliver parts on time.
My guys at Gurit and Koko’s Collision Repair have been hard at work ever since we announced the project, fabricating molds for my weight-reducing carbon fiber parts. As I said in my first post, weight is one of the huge performance factors at Pikes Peak. The road to the Peak is straight up with dozens of hairpins littering the hillside. The less mass you have to haul up the hill, the quicker your car will be.
With those basic physics in mind, replacing as much of the stock body parts in carbon fiber became a priority. That is much easier said than done, as making anything out of carbon takes a huge amount of talent, money and especially time. I am personally well short of all three. Gurit and Koko, thankfully, can provide copious amounts of at least two out of those three. Hopefully they’ll get us over the line.
Having a Tier 1 industry supplier like Gurit (Tier 1, as in supplying major manufacturers not just individuals like me) on board is like having a royal flush with an ace the hole and a rigged deck. Gurit supplies carbon prepreg material and body panel parts to some the best of the best in the automotive industry. They know their stuff when it comes to making carbon parts.
I can’t overstate how massively important this is with our short timeline. I don’t mean just with the carbon parts, but with every shop, builder and supplier we’re working with. Knowing the best and most efficient way to make things that work straight out of the gate is the only way we are ever going to get to the race on time.
In the case of my carbon parts, I leaned heavily on Gurit’s National Prepreg Sales Manager, Scott Schuster, to lead the charge. Scott’s been around the composites industry for literally decades and has the knowledge to get things done in our tight timeline. The first thing Scott did was call up Dallas, TX based Koko’s Collision Repair and got them working on making molds.
For high volume, highest quality, and perfect fitment, original equipment manufacturers usually make molds for carbon parts out of machined stainless steel. Stainless steel holds up the best under the high pressure, high temperature environment of an autoclave. For lower volume part runs, molds can also be made out carbon fiber, which holds up fairly well but doesn’t give you quite the same advantages as stainless steel. In our case, we were making one-off (two-off, actually) parts and needed them as soon as possible. Also, we had no money. Both of the above molds weren’t an option.
Scott suggested the guys at Koko’s make the mold out of vinyl ester, a hybrid of polyester and epoxy resins, strong enough to survive the heat and pressure of an autoclave (at lower settings) without failing. Vinyl ester molds are quicker, easier and cheaper to make than steel or carbon fiber molds, but they still produce good quality parts. The only issue is vinyl ester molds usually only last for a few runs before they are no longer useable. As we only needed a couple sets of parts, this strategy fit our needs perfectly.
The second saving grace working with Gurit was that they stock their material in the U.S., meaning we could get exactly the right material for the job without having to wait weeks for international frozen shipping. Yes, prepreg carbon material has to be shipped frozen to maintain the integrity of the infused resin. That’s not a cheap option. Once again in the tight timelines of motorsports and specifically our project, Gurit’s vinyl ester work was a life saver.
Originally we wanted to replace every body panel of the Z06 with carbon, but time would not allow it. As the biggest culprits in the weight area were the doors and the rear deck lid, those were first up on our hit list. We also decided to re-do the the T-top roof panel and the hood as well. They are the next-highest panels on the car, and the higher the weight is placed on the car and the farther it is from the center of mass, the more negative effect it has on handling.
We are guesstimating savings of around 35-40 pounds per door and 15 pounds for the rear deck lid. The hood is already made of carbon so we are not expecting a huge savings from that or the T-Top, 5 maybe 10 pounds tops. All in all, we’re figuring an almost 100 pound weight savings, which is nothing to sneeze at.
Our original plan has also included reworking a majority of the body panels for better aerodynamics, cooling flow, and aesthetics. Our short timeline nixed that plan as well. It would be far easier for Koko’s to just take the stock panel and make a mold out of it than to have them spend weeks doing design updates to the parts, before being able to make the molds.
As it was, the boys at Koko’s had to pull double duty just to get the parts out to us as promised and on time. That leads us to UPS, which did the exact opposite.
As of this writing we have still not received our parts, as they are sitting at an airport somewhere in Kentucky (how parts leaving from Dallas and going to Denver, end up in Kentucky is beyond me).
We are a week out from the start of practice for the Hill Climb.
We still have to chase down and then install our carbon parts and aerodynamics, make it to the dyno to get the engine tuned for power and high-altitude running, do a second electronic shake down and finally do an actual test day (or two) to get the car working the way I need it to tackle one of the most dangerous roads in the country.
I sure am glad this is fun, because otherwise it’d be a pretty shitty 9 to 5.