True SStreet with a totally new front suspension courtesy of TRZ Motorsports and Chris Alston's Chassisworks, along with a beautiful set of front wheels from Billet Specialties wrapped in Mickey Thompson rubber. With our G-body getting close to what resembles a complete roller, it was time to install the 10-point roll cage and finish the required steps out back to install our Chris Alston's Chassisworks anti-roll bar and coil-over conversion kit.
According to the 2008 NHRA Rulebook, a roll cage is mandatory in any vehicle running 9.99-seconds or quicker in the quarter-mile. Cars requiring a roll cage must be inspected every three years by NHRA and have a serialized sticker affixed to the cage before participation. Most sanctioning bodies generally follow NHRA rules, however it is always good to check out your local track or sanctioning body's rule requirements first.
The NHRA also specifies that all cage structures must be designed in an attempt to protect the driver from any angle-360 degrees. All chromoly tube welding must be done by approved TIG heliarc process; mild steel tube may be done by either the TIG or MIG wire feed process. Taking it a step further, a ribbon-type or SFI Spec 27.1 mesh-type window net is also mandatory on any full-bodied car requiring a roll cage.
Building a car that will break the 10-second barrier in the quarter-mile brings on an entire new set of rules and regulations when it comes to safety. Besides the aforementioned roll cage and window net, a quick-release, 3-inch driver restraint system with a 2-inch crotch strap is also mandatory, and must meet SFI Spec 16.1. Additionally, restraints are required to be recertified in two-year intervals. When breaking into the 9s, the driver must also obtain a special NHRA competition license, as well as additional driver safety equipment including a fire jacket, fire pants, fire shoes, neck collar, gloves and an approved helmet. Licensing and driver apparel will be covered in a future issue.
Before tearing into our 1987 Monte Carlo SS, we had to unpack the 10-point chromoly roll c
While many chassis shops can bend a custom cage from raw material, we chose to call the professionals at S&W Race Cars in Spring City, Pennsylvania, for a little direction in the matter. S&W suggested that we utilize its 10-point roll cage (PN 11-1516CM), which comes pre-bent per application and shipped to your door. Despite some minor trimming and notching, the cage is pretty much hold and weld. We opted for the chromoly unit, as it is lighter and stronger than mild steel. The reason for the weight savings utilizing chromoly in a roll cage application is attributed its strength. A 1 5/8-inch chromoly tube with a .083-inch wall thickness is mandatory for use, while a 1 5/8-inch mild steel tube with a .134-inch wall is mandatory causing excess weight. S&W also provided us with a window net mounting kit.
Here, all-purpose man Donald Singer sets in our aluminum Kirkey Race seat for measurements. The main hoop of the cage needs to be within 6-inches of the driver/seat. Once the proper locations are marked Donald begins to open up the floor via a hole-saw. Any vehicle with a full frame must have the cage welded to it and not the floor, as per NHRA rules. All metals to be welded to must be cleaned thoroughly via a grinding disc of some sort.
Next, master welder Mark Manieri tack welds the cage into place for fitment. Once satisfied, final welding can commence. Here is a little trick used at Half Scale: Once the front bars are welded, the back tack welds are broken free to continue welding fully around the bar, thus alleviating the need to remove the windshield. Since this is chromoly, it must be TIG welded all the way around or the cage will fail NHRA inspection.
Summit Racing Equipment in Tallmadge, Ohio, was called upon to supply us with a plethora of safety and interior items. First up was a set of Kirkey aluminum seats with cushioned black covers. The seats will help with a significant weight savings, great looks, and added safety through rigid construction. Next we opted for a pair of Simpson Racing harnesses to keep us planted in the seat at all times.
While our Strange Engineering brake system should be more than adequate in the stopping department, we also obtained a Simpson Skyjacker drag chute if additional assistance is needed and because the rules indicate we need to have one on board for our sub-9-second trips. And finally we snagged a nice looking chrome MaxOut fire extinguisher to have aboard, just in case a fire breaks out in the cockpit.
Now that the trunk was packed with goodies, we headed off to see Randy Ditzel and crew at Half Scale Dragster, a division of Race Specialties, Inc. Half Scale is located near the Pennsylvania border in Phillipsburg, New Jersey. Some of you may be familiar with Randy as he and the late Vincent Napp pioneered the Junior Dragster movement. Today Randy and the crew at Half Scale mainly focus on creating new technology and keeping at the top in Junior Dragster fabrication, but still enjoy working on the occasional full size vehicle when called upon.
Let's get welding.
In the end, the consumer with above average skills and some specialty equipment can probably do the installation of the roll cage and the coil-over conversion, although we opted to let a professional do the work. When your life is on the line, as well as your opponent's life, an experienced professional is definitely the way to go. Once again, be sure to understand what you are getting into through research, and check your sanctioning body's rules for additional clarification.
Stay tuned, as future installments will have us performing a frame notch to allow fitment of our Billet Specialties Street Lite wheels out back and the installation of our fuel system from Aeromotive, Inc.
Depending on the vehicle, the door bars can be custom bent to your liking. Randy bent our bar out slightly near the shoulder area and then a more pronounced bend toward the bottom so that we can retain the stock door panels, handles and armrests. Randy uses a 1 5/8-inch hole saw in the drill press to notch the bar as needed.
It was now time to move to the trunk. Randy had altered the rear trunk bars, which are ready to install through where the seat back would normally reside. At our request, Randy specially bent the bars to go through the speaker deck so we can retain our back seat for the occasional passenger, as crazy as that may sound.
Now that our cage is installed, Randy began installation of the R.J.S. window net obtained from Summit Racing. For ease of installation, S&W sent us this nifty window net mount kit. Installation was rather simple, but does require some welding.
Next Mark climbs under the G-body and begins installation of the adjustable lower shock mounts from Chris Alston's Chassisworks. Once the mounts are installed and the car is set at the desired ride height, Mark welds the tabs to the coil over cross bar and welds the bar in between the frame rails. For added rigidity, Randy had Mark add a piece of flat stock between the car and the upper frame section, which also ties into the rear cage bars.
While Mark was hard at work, Donald began assembly of the VariShock coil over conversion. CA Chassisworks suggested that we start with a 175lb spring in the rear and may need to go with a 225lb at a later date (depending on rear weight and squat at launch). The VariShocks will provide us with the ultimate in adjustability with a dual setting for both rebound and compression. Once the shocks were assembled and installed, we now have a completed coil-over conversion. Looks awesome!
We'll now begin the installation of the G-body-specific anti-roll bar. If you remember our Fab9 housing was fabricated with an integrated tube for this unit. Once the polymer bearings were pressed in, the 48-spline bar was slid into place and the billet aluminum arms were installed. The ARB will dramatically reduce body roll on launch giving us a better 60-foot time, hence a better e.t. Chassisworks gives very specific instructions, along with tips on adjustments.
As you can see here, the frame needs to be notched as per the instructions and the end-link brackets are then welded into place. Finally the end-links are installed and voila, we have a completely installed rear ready for action.
After hitting up the local Home Depot, we obtained these sheets of 22-gauge sheetmetal. This sheetmetal will be trimmed and properly formed to cover the holes around the cage. We'll seam seal these at a later date for a tighter seal. You can use clear caulking if you prefer.
Do to strict deadlines we were unable to perform a full installation on the Kirkey Race seats (PN KIR-41700), along with the Simpson Racing Harnesses (PN SIM-29108) from Summit Racing. We'll more than likely try to bolt the aluminum seats to the stock seat tracks and see how that works out. Normally with a little creativity it isn't much of a problem with simple hand tools and the fabrication of a few custom spacers.
Pictured here is our Skyjacker Drag Chute (PN SIM-42020BK). We'll devise a way to install this unit without putting any holes in our bumper or in the tail panel of our Monte. Once mounted we'll have to route the Summit Racing parachute release cable (PN SME-6000) in a civil manor, as well as install our MaxOut fire extinguisher (PN HTR-MX100C).
Half Scale Dragster
Summit Racing Equipment
P.O. Box 909
Chris Alston's Chassisworks
8861 Younger Creek Dr.
500 Shawmut Ave., Dept. SC
S&W Race Cars
11 Mennonite Church Rd.
Kirkey Racing Fabrication
Simpson Race Products