ACP department heading TECH
InTheGarageMedia.com
mechanic Jason Scudeller sits in car
Harnessing Safety
ADDING ADDITIONAL RESTRAINT TO A VINTAGE CHEVY
BY RYAN MANSON Photography by Jason Scudellari
W

hen it comes to safely securing the human cargo in a pre-’70s Chevy, it’s rare to find an option that improves upon the basic lap belt. Vehicle designs of the time were more based on styling than safety, so when it comes to upgrading the restraint system in a vintage Chevy, one’s often faced with some daunting decisions. Such was the case when Jason Scudellari was bolting together a 1963 Chevy Nova for his wife, Randi. The lack of B-pillars in the hardtop meant even something as simple as mounting a traditional three-point shoulder restraint was out of the question. One of the motivations behind the build was to take it to track days and autocross events, pushing the supercharged LS engine through its rev range and around the course. That said, Jason decided that the safety of its precious cargo would be paramount, and a pair of lap belts just wouldn’t do.

While perusing his interior options with TMI Products, Jason spotted their Pro-Chicane Series bucket seats. Knowing that the provided bolster support would be perfect to keep the occupants planted, it was the shoulder harness cutouts that got the wheels turning. A separate conversation with Craig Morrison at Art Morrison Enterprises and Jason had the solution to his safety problem. Jason mentioned his idea for a simple harness bar, mounted to the floor behind the front seats to act as the upper mounting point for a four-point harness system from G-Force Racing Gear. Morrison recommended taking things a step further by incorporating the harness bar with a full rollbar that will span the entire height and width of the interior of the car, providing further safety for the occupants. To support the rollbar, a pair of removable door bars would be incorporated, as would a pair of rear support tubes, connecting the top of the rollbar with the rear floor of the Nova’s body. It should be noted that while this setup definitely adds a degree or two of safety to the vehicle, building a full rollcage that met the specs of any sanctioning body was not the intention.

With a plan in place, Jason then headed to the shop, measuring tape in hand to get a laundry list of dimensions from the Nova to Morrison and the crew at Art Morrison Enterprises so that they could bend up the necessary tubes for the harness-bar-cum-rollcage design. The guys then took those dimensions and bent up the tubing, leaving things a little long so that Jason could trim each piece of tubing to fit nice and snug inside the confines of the 1963.

Upgrading from a simple set of lap belts to a four-point harness with a rollbar ended up transforming Randi’s Nova from ’60s-era safety appointments to a more aggressive, performance-minded design. The side and thigh bolsters of the TMI Pro-Chicane seats, combined with the security of the G-Force Racing Gear four-point harness, provides the ultimate race-inspired upgrades to ensure the occupants stay safe and stay put no matter how hard the Nova is pushed through the turns.

car with bent steel tubes near by, prepared for installation
1. Jason Scudelleri gave the crew at Art Morrison Enterprises a handful of measurements from the Nova so the guys could bend up some 1¾ -inch diameter 0.134-inch wall mild steel tubing. The harness bar will also double as a rollbar with additional support tubes tied to the rear of the body as well as a pair of door bars to provide some side-impact protection.
a plate is measured and modified to fit car's floor
2. There are six attachment points for the harness bar assembly, all using the provided plate from Art Morrison Enterprises. Here, one of the plates has been modified to fit the contours of the Nova’s floor and is being positioned to fit prior to being welded in place. These plates offer a stronger connection between the tubing and the car’s sheetmetal to prevent separation in the event of a crash.
view of rollerbar/harness tube installed inside car
3. The rollbar/harness tube will be installed first. A few careful measurements are made before the main hoop is trimmed and checked for fitment.
the hoop is checked for level
4. The hoop is also checked for level.
view of tube bottom tacked to mounting plate
5. Satisfied with the fit, the bottom of each tube is then tacked to the mounting plates on the floor.
mechanic measures door bars for fit and modification
6. Next, Jason turns his attention to the door bars. These need to be trimmed to fit by about 8 inches so as to inhibit ingress and egress as little as possible.
view of installed door bar
7. The top of each door bar will also need to be trimmed to meet the rollcage.
mechanic tests the placement and level of door bars before tacking
8. With the door bars trimmed, it’s time to mock things up and get them tack welded together. Care is taken to ensure the lower section of each bar is level with the floor of the car.
close view of tube connector weld-in bungs
close view of tube connector and tube
9-10. While the door bars will be relatively free and clear when it comes to the driver and front passenger, access to the rear seat will be challenging with the door bars in place. The solution is to make the door bars removable by using these tube connector weld-in bungs at both ends of the bar.
view of upper door bar tube connector installed and ready for welding
11. Here, the upper door bar tube connector is installed in place and ready to be welded. Note the short section of coped tubing that will be welded to the rollbar hoop.
mechanic prepares to install tube connector on the floor end of the car
12. The floor end of the door bar will receive the same treatment.
passenger side view of door bars installed
13. Here are the finished door bars fully welded and bolted in place.
mechanic measures back of car seat
14. With the rollbar securely attached to the car, Jason is now ready to install the actual harness restraint bar behind the TMI front seats. TMI’s Pro-Chicane series seats feature extensive side and thigh bolsters, perfect for keeping your body firmly planted while tearing up an autocross course, but even better for Jason’s application are the shoulder belt cutouts that allow a more aggressive, racing-style harness where a simple lap belt won’t suffice.
mechanic measures and marks placement for harness tube and rollerbar tube
15. The shoulder belts need to be mounted level to a maximum of -20 degrees past horizontal for proper effectiveness. Using this information and the height of the seat harness cutouts, the location for the harness tube can be determined and the rollbar tube marked.
view of harness tube clamped in place and checked for level
16. Trimmed to fit, here’s the harness tube clamped in place and checked for level.
close view of installed tube connectors
17. Once again, access to the rear seat is inhibited by the new harness bar, so another pair of tube connectors will be used here as well.
mechanic marks tubing with sharpie
18. Two more sections of tubing and the harness bar/mini rollcage is complete. Art Morrison Enterprises recommended adding a couple sections of tubing for added safety over what was to originally be a simple rollbar/harness tube. This last pair of tubing will connect the rollbar with the rear trunk floor of the Nova.
mechanic cuts tube end with a hole saw
19. A must-have tool when it comes to working with tubing is a hole saw that corresponds to the diameter tubing you’re working with and a good tubing notcher, both of which are available from Art Morrison Enterprises.
mechanic holds cut tube end to the rollerbar
20. The importance of a properly coped tube is apparent here where one of the trunk bars mates to the rollbar.
view of installed and painted door bars on driver side of car
21. From this angle, it’s easy to see how the simple door bars add some side-impact protection with minimum cabin intrusion, while also adding further support to the roll-/harness bar.
installed car seat with G-Force Racing Gear Four-Point Harness
22. A G-Force Racing Gear Four-Point Harness is used to keep both the driver and passenger safely strapped to the TMI seats. The lack of any kind of shoulder restraint in the hardtop Nova makes it hard to use anything other than a simple lap belt without similar modifications to what Jason has made.
view of shoulder straps attached to harness behind front seats
23. Attachment of the shoulder straps to the harness tube is accomplished by simply wrapping the straps around the bar and securing the ends, as per G-Force’s instructions.
Duralast Tech Center box
SOURCES
Art Morrison Enterprises
(800) 929-7188
artmorrison.com
G-Force Racing Gear
(770) 998-8855
gforce.com
TMI Products
(951) 272-1996
tmiproducts.com
view of shoulder straps attached to harness behind front seats
23. Attachment of the shoulder straps to the harness tube is accomplished by simply wrapping the straps around the bar and securing the ends, as per G-Force’s instructions.
Duralast Tech Center box
SOURCES
Art Morrison Enterprises
(800) 929-7188
artmorrison.com
Comp Cams
(800) 999-0853
gforce.com
TMI Products
(951) 272-1996
tmiproducts.com