Safer at Any Speed Part 3:
Take Your Seat
By Brion Gluck
Everybody's heard at least part of the old song "Dem Bones," you know, "the neck bone's connected to the head bone." The safety systems for your racecar are the same as the bones in the song; they're connected. The harness works with the seat works with the roll cage works with the rest to keep you protected in a crash.
One weak link in this chain of systems, and you may not be able to sing about your head and neck being connected anymore. So why do so many people equip their cars with top-dollar harnesses and then plop their rear ends into a cheap, improperly mounted racing seat? If the seat comes loose, not only is the harness not going to protect you, you may have real trouble keeping the car under control on the track.
"A seat's function is to hold you in the car laterally. Everything is dealing with centrifugal force, right or left," said top NASCAR seat supplier Brian Butler of ButlerBuilt Motorsports Equipment (http://www.butlerbuilt.net, 1-800-621-SEAT.)
Holding your body in place is more difficult than it looks, since your head, shoulders, hips and legs all move independently. Depending on the kind of racing you do and your car, you may want or need extra support in specific areas.
"The whole seat needs to fit properly, but it has to work in concert with not only the car but the pedal position, the steering position, having proper arm freedom to shift, operate the car in a way that is comfortable," Butler said.
A dedicated racing seat supplier like ButlerBuilt or Kirkey Racing (http://www.kirkeyracing.com, 613-998-4885) can offer specific advice and help for particular applications and preferences, but there are some general things everyone should know when selecting a seat.
First, you have a choice of basic materials for your seat. Commonly available are plastic and aluminum. For suppliers like Butler, this is really no choice at all. Well-made aluminum seats are superior in their stiffness and durability, and that means both a safer and more comfortable seat. If you can afford to pay a little extra, aluminum is clearly the way to go.
Butler recommends looking for a minimum of 1/8th -inch wall shell construction in the seat for road race and oval track applications.
"Thinner is terrible, too weak and they don't support you properly. Your performance and safety envelope will suffer. Not might suffer, will suffer," he said.
Make sure that the aluminum is a quality alloy, not too soft and not too hard. You can't tell just by looking at it, so ask your supplier what grade and temper is being used. The welding quality is also something to watch, according to Butler. "I've seen aluminum seats come apart at the welds."
After you've selected a seat, you need to plan to mount it properly.
"The most important mount in any seat system is at the shoulder level at the seat back," Butler said. "You need to have a proper mount into the main hoop of the roll cage. A lot of people put a tremendous amount of effort in putting the seat bottom in. They think all of their weight and all of the forces are applied through the seat bottom. But the bulk of your body weight is centered in the chest cavity." Some sanctioning organizations, like SCCA, mandate particular bracket systems to be used for the seat back attachment.
Not that the seat bottom isn't important, too. For stock floorpan installations like a Mustang, many suppliers recommend augmenting the factory metal with welded load-bearing brackets to help distribute the loads over a wider area.
NASCAR teams even tie the bottom mount of the seat into the door bar of the roll cage, so that the seat and driver are pushed away from the point of impact if hit in the side. Most amateur racers won't need to get that elaborate, but make sure the seat is mounted rigidly using top-quality hardware.
"If a seat is able to break loose from its mounts, we've lost control of the situation," Butler said. "Not only is it unsafe, performance goes right out the window. A properly fitted and properly mounted seat is actually a performance enhancement. You'll go faster and you'll do it longer."
Want to be able to switch out drivers for endurance racing or to swap cars with a buddy? Better make sure you're both about the same size: A real racing seat isn't adjustable. That also means you need to think about basic pedal and wheel position issues before you go bolting things in, particularly in a production-based car like the Mustang where those positions aren't readily adjustable.
"You can't be safe and be quickly adjustable," Butler said. "No way that that's going to happen. Using padding or an insert is about all you can do, as long as safety isn't compromised."
Butler noted "nine times out of ten, the seat is the last consideration, when in fact it should be the first thing. First the seat, then pedal and steering locations and then door, roof and shifter location. Everybody does it backwards."
You should consider whether the seat position will give you proper headroom with your helmet on and have a good sight line down the track. For road racing, having around 20 degrees of recline will help give you enough knee bend to distribute forces and weight properly and will be more comfortable as well.
A properly-sized racing seat should be a snug fit. "When we custom-build a seat, if they change their weight more than 15 or 20 pounds, that seat doesn't fit anymore," Butler said. If you're sitting loose in the seat, you'll be moving around in your harness, and that's bad. The seat bottom should keep you planted in the bottom of the seat, controlling your hip and pelvic area.
You don't need a seat as padded as your mother's couch to be comfortable, even for long endurance races. "If the seat fits you, we don't need much foam," Butler said.
Seat suppliers have a range of add-ons to their basic seats that provide additional support for the head and legs. ButlerBuilt offers padded and upholstered leg supports for the hip down to the mid-calf.
"(The support) keeps the foot vertical on the throttle pedal, and keeps the shifter from hitting the leg, too," Butler said.
Head supports can help greatly in reducing fatigue during a long race, as well as offering some extra protection to the driver.
The bottom line: A high-quality racing seat is another one of those great two-for-one deals. You get a big increase in safety over a stock or "sport seat", and you also get something that is far more effective and comfortable in use on the track.