Last month, we covered the process of bolting in a set of Corbeau’s fabulously supportive A4 seats into Scarlett, our ’72 coupe project car. As well as the seats hold onto you, though, you still have to have belts to “snug you up” into them. Since this car is destined for track use, we ordered a set of Corbeau’s five-point harnesses along with the buckets. In this installment, we’ll cover what it takes to install them in a shark.
Consisting of five straps, or points, the harnesses combine a traditional lap belt with a pair of shoulder straps and an anti-submarine belt that comes from beneath the seat in the crotch area. The latter item is intended to keep the driver from sliding out from underneath the other belts in the event of a crash. While they are available in different sizes, our harnesses have 3-inch webbing for all but the anti-submarine belt, which is 2 inches wide. They’re rated to meet SFI specification 16.1 and come date stamped, as harnesses have to be replaced periodically to be used for racing. All the belts snap into the same latch arrangement, something that’s mandated by some track rules, since you may need to get out of them fast if you wreck.
The lever or “latch and link” configuration that’s been around for some time uses a lever-operated latch. It holds the two lap belts together, and the male tab on one lap belt passes through slots on the ends of all the other belts before being latched into place in the female end of the latch on the other lap belt. The more modern approach, however, is a camlock buckle, which lets each of the belts plug into a round buckle one at a time. Like the latch-and-link, all the belts are released at the same time when you rotate the buckle. While I’m all for old-school, it’s my opinion the camlock is a better system, which is why we specified camlock buckles for our harness. They work smoothly, and their black-and-silver construction looks great and fits in aesthetically with the car’s color scheme.
What follows is a step-by-step of the harness-installation process. Once completed, all that’s left is to do is slide in, cinch up, and roll out. The car may go all sorts of interesting places, but you? You ain’t going nowhere.
Author’s note: This article contains information on mounting safety equipment. The mounting techniques we used may not be suitable for your application, and thus the author and VETTE magazine specifically disclaim any liability that may result from following these instructions. If in doubt, consult a professional as well as the rule book of the sanctioning body where you want to race.
01 While the “latch and link” buckling system is still alive and well, we went with Corbeau’s camlock system, which uses a round central buckle. While each of the belts can be plugged into it separately, they are all released at once when the knob is rotated.
02 The five-strap harnesses combine a traditional lap belt, a pair of shoulder straps, and an anti-submarine belt. While they are available in different sizes, our harnesses have 3-inch webbing for all but the anti-submarine belt, which is 2 inches wide.
03 For added comfort, we also used a pair of Corbeau’s logo-marked harness pads. Made of neoprene, they wrap around the harnesses and are held in place by Velcro, so they can be installed and removed without the need to remove the harness itself.
04 The harnesses come with a tab at either end. The larger one, shown here, has a 0.5-inch hole and is used for mounting the harness in the car, while the smaller tab is the one that snaps into the camlock. Since the shoulder harnesses were mounted by wrapping them around the harness bar, we didn’t use the mounting tabs on them.
05 Mounting the inboard lap belt is simplicity itself: Back out the bolt holding the factory belt in place, then use a Grade 8 bolt (or, in this case, a metric equivalent) tightened to 30-45 lb-ft. Done.
06 To mount the outboard lap belt, remove the seats and door sill, peel back the carpet, and remove the factory seat-belt reel and its plastic cover. Snake the new harness through the seatbelt guide, then bolt the mounting tab into the old reel mount and torque it down to the factory spec of 30-45 lb-ft.
07 Once the outboard lap belt is bolted into place and routed under the seatbelt guide, slip it back through the carpet. Since the carpet had already been cut for the factory belt to pass through, I only had to use a razor blade to lengthen the slot in the carpet for the wider harness to fit.
08 From the location of the shoulder harnesses, it should be obvious that they have to mount to something, and that something will not be found on the back deck (or window frame) of a stock C3. We used a Shark Bar from Vetteworks, which mounts the harnesses at the proper angle relative to your body.
09 The Shark Bar provides a secure mounting point for the harnesses, and has a welded-on retainer that keeps them from sliding from side-to-side. It requires virtually no modification to install, doesn’t interfere with removing the rear window, and is available in a black-crinkle powdercoat that blends well with the car’s interior. (Other finish options are available as well.)
10 Part of the Shark Bar system is a pair of lateral support anchors that, along with a strut, help brace the already-solid bar to the car’s subframe. There’s a left and a right (shown), and they’re conveniently marked as such.
11 Start by removing the window trim and sail panel, which will give you access to the part of the subframe where the lateral support anchors mount. To get all this out, you’ll basically be removing all the interior panels in the rear of the car, which sounds more daunting than it is.
12 The rear-window area after the trim is removed. While you have to take it out to remove the sail panel and install the lateral support anchors, you’ll want to reinstall it before putting the Shark Bar in place—otherwise, it ain’t going back it.
13 You’ll need to remove the interior roof panels to get the sail panel out. This requires removing the T-tops to gain access to this screw near where the upper rear corner of the window would usually sit.
14 The sail panel is also held in place with this strip of trim found inside the door openings. If you’re envisioning a lot of small interior screws lying around, you’ve got it right.
15 The backing plates for the lateral support anchors slip into place in the subframe, on the backside of the holes you see here. The anchors then bolt to them through the subframe holes.
16 We had to modify the anchors a little to get them to slip into place where they could be bolted to the anchors. With that done, they were bolted securely to their backing plates, sandwiching the subframe between the two parts. Trim the carpet around the anchor and start reinstalling interior panels.
17 The carpet does have to be trimmed around the lateral support anchor, but only slightly. Should you wish to remove the bar, this, and a pair of holes on the back deck, are the only things left behind.
18 The Shark Bar will mount to the bolt holes that would usually hold the retractor for factory shoulder belts; the bolts are easy enough to find once you peel back the carpet, as they are quite large.
19 After removing the bolts from their location under the carpet, we used an awl to probe through the carpet to find the bolt hole. We then opened up the hole so we could fit the harness-bar mounting bolt through it.
20 Once the included 0.5-inch bolt will fit through the carpet, put the bar in place and install the two bolts into the holes you located on the back deck. They’ll be torqued down later. For now, just install them, followed by the struts, with the Heim joints downwards.
21 The bar, braced and fully assembled. You’ll likely need to adjust the heim joint at the bottom of the strut rod to get the length correct. All bolts attached to the harness bar should be torqued to 25 lb-ft; all others, 30.
22 With the bar torqued down, the shoulder harnesses can be threaded into place on the bar, under the loop that keeps them from sliding too far to one side. Follow the mounting instructions: The end of the harness should run out of the slider, over the bar, back into it, and then be looped over the top of the slider and run back through.
23 The Vetteworks mounting bracket for an anti-submarine belt, which bolts into place on top of the brackets that hold the factory seats in place. Because it’s designed for stock buckets, it interfered with our A4s’ fore-aft adjustment bars. Fortunately it also allows you to route the belts over the front of the seat, which is what we’ll be doing.
24 In the absence of more-specific guidance from the NASA, SCCA, and other rulebooks, we chose to mount the anti-submarine belt to the seat bracket, which is made of welded flat stock and bolts to the seats’ factory mounting points.
25 Since it’s important for the anti-sub belt to be centered—to prevent your body from pivoting around it—we measured the seat bracket from side to side, and spotted a hole in the middle of the rear bracket.
26 We then used a series of drill bits to start the hole, gradually enlarging it to the required 0.5-inch. If you do this without removing the bracket from the seats, consider covering the seat to protect it and backing your hole with something like this piece of wood. This will keep you from punching your bit through the bottom of the seat when it breaks free.
27 With the holes drilled, we bolted the anti-submarine belt’s mounting tab to the mounting frame, again using a hardened 12mm bolt with a washer and nylock nut.
28 Unlike the lap and shoulder belts, which you cinch into place once they’re buckled, the anti-sub belt can’t be adjusted when you’re seated. We adjusted it for length before putting the seat back in the car.
29 All the belts in place after final assembly. All that’s left is to get in the seat and strap them on.