[Editor's Note: This article originally ran in the April 2008 issue of Grassroots Motorsports; for more updates, visit here.]
A project car will reach critical mass at one point along its development path and then explode into a fury of progress. You could call it a watershed moment, a turning point, or merely the minute where you look out in the driveway and can finally envision the car in its finished form.
After six months of ownership, we have finally taken our Saab 99 from ratty driver to something approaching a real rally car. We have reached the point where we can picture the car tearing down a dirt road or storming through the gravel. Now it’s time to make it safe.
Safety preparation is a major undertaking in a rally car. While car-on-car violence very rarely happens in stage rally competition, there is precious little runoff room on those special stages. A rally stage will typically consist of a twisty road—often gravel—that is lined with plenty of trees, rocks and cliffs. As a result, any deviation from the desired path can make for a rather eventful situation.
Adding to this danger is the fact that the safety and EMS personnel aren’t waiting at every turn in case something goes wrong. It can take up to 15 minutes for the safety crew to reach a wrecked car. As a result, teams need to be proactive until help arrives—or help other competitors who have run astray. That means a cage and a first-aid kit, among other things.
The first step in constructing the roll cage is to strip out the entire interior, including seats, carpet, headliner and the stock seat belts. We even took the time to use blocks of dry ice—solid carbon dioxide—to thoroughly chill the steel floor plan so we could easily crack off the asphalt-based sound deadening material that covers just about every internal panel of the Saab.
Removing this goo creates a cleaner surface for any welding, and it lightens the car considerably. It also promotes a much cleaner appearance once the cage and interior are repainted.
Next, the glass was removed to make the roll cage construction easier. This step would also protect the glass itself from being damaged during cage construction; welding and grinding throw off very hot sparks that can pit the glass.
Our roll cage was built with the help of Mark Stewart from Kirk Racing Products of Mount Olive, Ala. Mark has established a reputation for building safe, high-quality roll cages at fair prices. Duplicating our cage would cost about $2000, which we feel is more than reasonable for the amount and quality of the work involved. It took about three days to build the Saab's cage, including several late nights and early mornings of work.
Mark started the building process by reading over the applicable rules and discussing the design considerations with us. We wanted a cage that met both NASA RallySport and Rally America requirements. While both groups use nearly the same specs, there are some wording differences. Rally America’s rules mirror those of the FIA, while NASA has sought to rewrite the European sanctioning body’s tortured French-to-English translation by producing a simplified and easy-to-understand rule book.
Stage rallying usually involves more stringent safety specifications than road racing, and going beyond the minimum is often allowed. For example, where most road racing rules specify a maximum number of roll cage attachment points, that’s not the case when it comes to rally. You can weld the cage to the chassis as much as you’d like. You could even extend the cage forward to support and strengthen the front suspension, something that’s often prohibited in amateur road racing.
Our minimum cage specs required at least six attachment points to the car’s shell. An X-brace for the main hoop was also required. We needed a series of door bars on both sides, a dashbar extending under the steering column, and diagonal bracing between the rear down tubes. There also had to be roof supports.
Welding the mounting pads to the chassis is one of the most time-intensive portions of the cage build.
The front pads tie the sill and the wheel well together.
Mark lays out the main hoop on the ground using a tape measure, protractor and chalk.
The main hoop is then fitted to the car.
The rules required reinforcing gussets at several junctions, a job we could do two different ways. We could either weld in short sections of tubing or wrap sheet metal around the bars to form a gusset.
Once our cage design was finalized, the time came to start making sparks fly. First, we had to prepare the car’s unibody to receive the cage. An abrasive disc pad fitted on a die grinder quickly removed the paint. Quarter-inch steel plates were then cut to fit these areas.
Mark likes to tie the plates for the main hoop into the car’s sills on more than one plane. Each attachment point will usually feature one plate welded to the floor adjacent to another that runs the sill vertically. The mounting plates for the remaining supports follow a similar construction method, as the goal is to tie the cage to as much of the car as possible. Cutting and fitting these mounting pads—usually at least six, and eight in our case—takes about a quarter of the total time needed to build a cage.
The main hoop is then bent and fitted, followed by the tubes that extend forward and then down to the front foot wells. Mark tack welds the main hoop to its mounting pads and then fits the front downtubes. The downtubes are tacked to the bar that spans the top of the windshield. He then tacks in the two roof support bars.
At this point, the tack welds at the junction of the main hoop and downtubes are broken so the front section can be pivoted down, allowing a complete 360-degree weld to be achieved. The front section is then fitted back to the main hoop and everything made thus far is welded solid to the mounting pads. Next, we drilled holes on each side of the Saab’s firewall so we could run tubes forward to the tops of the front spring perches.
The rear downtubes were fitted and tacked to the main hoop, as were another pair of tubes that formed a V in the back section of the cage. This V would back up the V fitted to the roof, creating a very strong structure to help fend off a hard collision. These joints were then fully welded before Mark fabricated and attached the main hoop’s X-brace.
With that done, all that was left to build were the driver and passenger door bars. In addition to the bars that run along each sill, we ran a pair of crossed bars across each door opening. These were done last since they essentially close up the car and make it tougher for the fabricators to get in and out.
By the end of our three-day stay in Alabama, our Saab had a solid cage. However, we still had some detail work to do once we got home.
While the cage build itself required specialized equipment like a mandrel bender and a high-powered, 220-volt welder, the smaller details like adding additional gussets to the chassis and building seat mounts could be done in our garage with our smaller 110-volt, 140-amp MIG welder.
The first item on our to-do list was to make gussets for the A- and B-pillars from 16-gauge plate steel. These gussets would tie the unibody to the cage so that a light roll wouldn’t bend the body too badly. (In theory, these extra reinforcements would also allow us to replace any glass without having to reconstruct the window opening.)
With the main hoop in, it’s time to work on the front portion of the cage.
Then we’re onto the rear section; here Mark fits up the rear V.
Once everything is tacked into place, it’s welded up solid.
After we got the cage home, we made gussets that were strengthened with this dimple die.
The finished gussets tie the cage into the shell along the pillars.
Adding material to the cage also adds heft, so to minimize any weight gain we lightened each gusset with a series of 3/4-inch holes. We further strengthened the gussets by bending the edges of the holes downward with a dimple die. The dimpled holes look pretty badass, too.
Before we painted the cage, we also welded up a series of steel brackets that will serve as seat mounts. We first approximated where our butts needed to be relative to the pedals and steering wheel. Then we used the typical 12-inch length of seat side rails to determine where the seat mounting points were going to go. We factored in some wiggle room to fine-tune the position after the seats are fitted.
Next, we sprayed the entire cage with Rust-Oleum Professional Series gray primer and allowed it to dry. We then had a quart of our Saab Antelope Brown paint mixed up and injected into trusty Nason fill-in reducer cans, just like the ones we used to paint the car’s exterior.
After quickly running through the first quart, however, we had Higgs Auto Paint mix up a second quart. Painting a roll cage involves a lot of waste, as only a portion of the spray actually hits the thin tubing. After the paint dried, we protected the door bars from chips and scuffs with strips of Lamin-x protective film.
As many of us have experienced while shoe shopping, what looks good on the rack doesn’t always fit so well once slipped on. That’s why you have to first try on shoes before plunking down your money. Racing seats are much the same deal, requiring fitting and testing before you shell out your hard-earned cash.
As for the rules, both NASA and Rally America require FIA-approved seats for the driver and navigator. While you can find some cheaper FIA-rated seats for less than $500, we went above and beyond for these vital pieces of equipment. While we do plan on using a HANS Device to limit any injuries from a head-on impact, we wanted seats that have integrated side restraints for extra protection in the event of a side hit or rollover.
To find the right seats for our situation, we sat in as many buckets as we could. Our physical build dictated a wider seat, as our hip bones and shoulders were sticking points in many of the standard-width buckets.
The Racetech RT4009WTHR fit us best. The T in the model number denotes that this seat was designed for taller drivers, yet it seems to also work well for those with taller than average torsos. No matter what the designation, the seat put our shoulder harness holes in just the right spot. For our co-driver, we chose the standard-height RT4009WHR.
Including the required mounts, the two Racetech seats set us back a little less than $2500 from ApexPerformance.net. They had a good selection of Racetech seats in stock and quickly shipped our purchases.
With all of the welding done, it was time to prime the cage.
After the primer cured, we sprayed the entire interior and cage with paint that matched the exterior of the car.
Our trunk showcases the ATL fuel cell, our tool kit and the spare.
We shielded our newly painted cage with Lamin-x film.
A first aid kit is a rally essential.
Good safety gear does not come cheaply, as the seats and cage accounted for half of this project’s entire budget. Considering that you can’t call time-out or press the Pause button when things go horribly awry, we consider this money well spent.
Before we could move on to something else, we still had to order a set of harnesses for the driver and passenger. Stage rally regulations require at least a five-point harness for the driver and passenger. Plus, those belts must wear an SFI or FIA approval rating; SFI-rated seat belts are good for two years from the date of manufacture, while FIA-rated belts are good for five.
While the latter are more expensive, they represent a better long-term deal. We chose a pair of Schroth’s Profi II six-point, FIA-rated harnesses for our Saab. The Schroth cam-lock has proved to be very easy to use, and the two antisubmarine straps are about as comfortable in the delicate areas as possible. The harnesses banged our budget back by another $315 apiece. Like we just said, we’ll gladly pay good money for top-shelf safety gear.
Now that our seat, harnesses and cage were in place, we could see which areas of the roll cage needed to be padded. The rules dictated that we use the stiffer FIA-approved pieces of energy-absorbing foam. We chose BSCI’s new dual-density foam segments, which run about $40 per three-foot stick.
The inner core uses the stiffer, FIA-compliant foam, while the outer section features a softer material. This setup provides approved protection during major spills but also gives some cushion during minor-league head or elbow bumps.
We padded the areas near our driver’s and navigator’s heads as well as the door bars. It took us three sticks to do the job.
While neither American rally sanctioning body requires a fuel cell, running one in place of the the standard gas tank is recommended. The fuel cell’s foam baffling and puncture-resistant inner bladder work to prevent and limit an explosive rupture of gasoline in the event of a crash.
In our case, several factors pushed us toward installing a cell. For one, the stock gas tank location in a Saab 99 is low in the chassis, hanging down behind the rear axle. If we kept the tank, we would have needed to design and fabricate a skidplate to block the rock spray. Another factor was the condition of that stock tank. While running new fuel lines we realized that the original tank had a small rust hole.
Finally, running a proper fuel cell is just plain safer, especially in a motorsport that involves yumping at high speeds past unforgiving trees and boulders.
We’re protecting our melons with several sticks of FIA-approved padding from BSCI. This particular type has two densities of foam.
The Racetech RT4009WTHR and RT4009WHR seats are comfortable and safe—perfect for rally.
Schroth harnesses keep us in place. They’re also FIA-approved.
Our seat mounts are mounted to the car with a combination of welding and traditional fasteners. The crossbars are welded in, while the side mounts are bolted to the crossbars. The result is strong and simple.
We chose a 12-gallon ATL fuel cell featuring a steel container and an internal electric pump. The fuel pump is mounted inside a smaller surge tank that’s within the main container, preventing sloshing and pickup problems at low fuel levels. The complete tank with pump cost us about $1250, but it was nearly a plug-and-play operation since we simply rerouted the positive and negative wires from our original pump to the cell’s pigtails.
For fuel lines and fittings, we chose Aeroquip’s Socketless fabric-covered AN6 lines. These lines are easy to cut and fit, plus they can handle several hundred psi of pressure without leaking. We hooked these lines to the 5/16-inch steel lines that we ran to and from the engine through the cockpit, where they should be safe from flying rocks.
Before we could wipe our hands together and move on to something else, we had a few more details to attend to. We still had to install our fire extinguishers, first aid kit and safety triangles.
As far as fire suppression goes, the minimum requirement is a bottle with a 10BC rating. We went beyond the minimum by installing two 10BC bottles, one mounted to the roll cage behind the driver and the other right in front of the navigator’s seat. We’ll probably go with a complete fire-suppression system eventually, but this will get us on course. If we do go with the complete setup, we’ll still keep one of the portable extinguishers in case we ever encounter a fellow competitor in need of assistance.
Since the nearest safety crews might be a few minutes away, all rally teams must carry a first-aid kit that is visible and accessible to the team itself as well as to those outside the car. (You never know who will be first on the scene.) Our kit came from Safe Drives, and we mounted it behind the front seats. Since our car is a two-door, reaching the kit requires a little bit of flexibility. Hopefully it will never be needed.
In the event of a breakdown or off, we’re also required to place three orange triangles behind our car to warn others of the situation. We placed one triangle in the navigator’s door pocket and strapped down the remaining two inside the trunk. Our thinking is that the navigator can quickly run back and place the first triangle while the driver is grabbing the other two. With cars coming along at one per minute, disabled teams need to act quickly to prevent a catastrophe.
The quest for safety never really ends and we are planning to add more equipment that isn’t required by the rules. A pair of window nets and an electrical cutoff switch are on our short list for future improvements.
Our Saab now has its proper safety gear, a reinforced suspension and a fresh coat of paint. It’s almost ready to experience some competition. We’ll soon detail the final tweaks plus that first taste of dirt.
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