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Cage Match - Installing a Rollcage in Our T-Top Fox MustangChris Alston's Chassisworks installs its eight-point, Pro-Street rollcage with an H-brace for T-tops on our Drag Week 1986 Fox Body Mustang Coupe From the July, 2006 issue of 5.0 Mustang & Super Fords By K.J. Jones Photography by K.J. Jones
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In last month's introduction of our Project T-top coupe, we mentioned that one of the performance goals we hope to achieve is for the car to run consistently in the 10s throughout the five days of Hot Rod magazine's Drag Week. A 10-second e.t. might be a bit conservative and off the pace this year in Drag Week's Power Adder Small Block class we'll enter, but if the stars align properly and we do get the car finished in time for Drag Week, hitting our target shouldn't be a problem. Our car will have plenty of Keith Craft and Paxton Novi power to carry it well into the fairly quick e.t. range if we dare to go there with it. With the 10s in mind, and because we're working with a car that leaves quite a bit to be desired when it comes to chassis soundness, we decided it would be best to tie the coupe together with an eight-point rollcage, as opposed to an eight-point rollbar (see Roll Rules sidebar). It's important to make any Mustang's overall structure as strong as possible if you plan to subject it to more than occasional 'strip action. In addition to strength enhancement, rollcages also provide safety for the driver and passenger, as the placement and size of the bars help protect a Mustang's occupants in the event of a side-impact, rear-impact, or rollover accident-on the street as well as at the track. Dismantling our project car's... Dismantling our project car's interior was the first order of business. Chris Alston Chassisworks' Sales and Project Manager Jim Wright asked us to have the coupe's interior completely gutted, with the dashboard assembly removed since we'd be installing 'cage sides that land behind the dash. With the help of Greg Montoya, and working at a fairly leisurely pace, the interior was stripped down to nothing in no time. T-top cars are, well, different. The two glass roof panels let the sun shine in, but they also represent a pretty big compromise in an already-suspect chassis structure. The potential for unibody flex/twist is much greater with a T-top car, especially when heavy doses of horsepower and torque are added to the mix. While preparing our project car for the Chris Alston's Chassisworks eight-point, Pro-Street rollcage featured in this report, we saw signs of chassis flex in the floorpan and driveshaft-tunnel area, just below the rear seat bottom. Despite not knowing our car's complete history, we don't believe it ever ran with anything more than a stock 5.0, so this is proof positive that it doesn't take a lot to get a T-top 'Stang's subframes crossed up. We presented our project concept to Chris Alston Sr., who owns and operates the Sacramento, California-based chassis-components empire that bears his name. Chassisworks is widely known as a one-stop-shopping outlet for hardcore race-car components, including bolt-in, FAB9 rearend housings and direct-fit, double-adjustable VariShock rear shocks and front struts for Fox Mustangs. And, like all the other participants in this project, Chris was immediately interested in getting involved and suggested several good ideas for making our coupe's frame a bit more solid. The car's carpet, seats, console,... The car's carpet, seats, console, door and interior panels, and such are in pretty bad shape. A complete interior makeover, featuring OEM-accurate reproduction pieces from Late Model Restoration Supply (www.50resto.com) is one of the many tasks that will keep us busy. We've all probably seen hundreds of street Mustangs with rollcages. What stands out about the 'cages in the first-generation Fox cars ('79-'86), however, is that most of them feature 'cage sides (the side tubes that run from the main hoop and alongside the top of the door frames, then down to the floorpan) that fall in front of the dashboard. These rollcages also do not include any bracing in the center area of T-top 'Stangs. We also wanted the 'cage sides to have enough clearance for access to the T-top latches. After explaining to Chris our interest in incorporating these elements into a rollcage for our project car, he suggested we go with an eight-point, Pro-Street rollcage (starting at $396) with optional through-the-dash 'cage sides for easier driver/passenger entry and exit. 'Cage sides that land in front of the dash and swing-out side bars are standard with the Pro-Street cage. It also includes an H-brace between the windshield brace and the main hoop, which supports the centersection of the roof. We discovered the buildsheet... We discovered the buildsheet for our rare Mustang after pulling the carpet. Years of soaking in oil from the funky aftermarket A/C unit that sat in the passenger-side footwell and other spills in the carpet had ruined the document. It was neat that the buildsheet was still there, but, unfortunately, there was no way we could decipher anything, and it was completely destroyed when we tried to lift it from the floor. We also expressed our interest in maintaining a rear seat in the Drag Week coupe. Sure, the rear seat is usually a deleted item on street/strip Mustangs, but we want to retain the seat, for a true, street-car look, and in the event we have to help out a fellow Drag Week participant with a ride at some point during the tour. The bent rear struts that are included with a Pro-Street cage kit do not impede the rear seat area, so even though the standard back brace (that runs across the width of the main hoop) will be welded in to comply with NHRA rules, there still will be enough room for a passenger in the back of our car. It's important to point out that some sacrifices usually must be made when dealing with anything that has even a small element of "custom" involved, such as our rollcage. In our case, by going with the optional 'cage sides that run through the dash, we'll probably have to make a few alterations to, or completely do away with, the HVAC ducts in order to achieve the clean look that we want. We've noticed that our 'Stang's heating system and blower fan look pretty sickly anyway, so the entire unit might be scrapped. Editor Turner better remember to bring a coat for the nighttime cruising. Going with this option might also compromise the fuse box. Through-the-dash 'cage sides are popular on '87-'93 Mustangs, with tubes falling through the area where the front speakers normally would be. The accompanying photos and captions provide an inside look at the overall effort that goes into developing a Mustang rollcage, from concept to actual product. As we learned during our three days at Chassisworks, it isn't as easy as one would think. Critical measurements, trial-fitting and refitting tubes, and even more measuring are all a huge part of this process. With trial-and-error and repetition, the finished product is something that's perfect for ours or any other 'Stangbanger's Fox. Chassisworks rollcages are available in mild-steel or chrome-moly. Read on and see how Sales and Project Manager Jim Wright, Production Supervisor Steve Collins, and Shop Supervisor Scott Wilkins collaborate on this mission to fortify our four-eye with a super-solid rollcage.  The heavy, tar-like, rubberized...  The heavy, tar-like, rubberized sound deadener on the 'Stang's floorpan must be completely stripped off before any welding can be done. We used this assortment of chippers, heat blower/torch, and scrapers to remove it.  This is probably the worst...  This is probably the worst part of installing a 'cage, but there's no way around it. Stripping the sound deadener is labor-intensive, so it's easier on your wallet if you do it yourself. A shop will probably charge quite a bit more if they have to do the cleanup for you. Take your time and be patient. The stuff really does come up.  After arriving at Chassisworks,...  After arriving at Chassisworks, Shop Supervisor Scott Wilkins and Production Supervisor Steve Collins position our coupe on four jackstands. It's important to have the car perfectly level prior to installing a 'cage. This helps ensure that measurements are accurate and that your 'cage won't wind up being lopsided or not squared inside the car.  Always remove the fuel tank...  Always remove the fuel tank before you start welding. Sparks and fuel (and even fuel vapor) do not mix. Steve removes the tank on our coupe and stores it outside the shop.  Each "point" of a rollcage...  Each "point" of a rollcage should be attached to a plate welded to the floor of the car. The number of positions where each tube lands at the floorpan, trunk/hatch, or engine-compartment framerail represent the total number of points...  ...This is primarily for support,...  ...This is primarily for support, as the floorpan and almost every other similar area of a Mustang isn't strong and a tube can easily break through if subjected to an excessive force against it...  ...In this photo, Scott inspects...  ...In this photo, Scott inspects the underside of the floorpan to determine where he will position each 11/48-inch square of steel plate that will be used as landing pads for the rollcage tubes. He then installs each plate...  ...The heat-and-beat technique...  ...The heat-and-beat technique is used to work the plates into the contours in the floorpan so that they are all flat and level. Once each plate has the right shape, Scott final-welds it into place.  All the primary tubing for...  All the primary tubing for the driver/passenger area of a Chris Alston's Chassisworks rollcage is CNC-bent and cut according to dimensions that are established by positioning templates at various points inside the car...  ...The templates represent...  ...The templates represent the outside radius of each bend in the main hoop and 'cage sides. These photos show Scott and Steve placing the templates in position and measuring the center-to-center distances between them...  ...The information is plotted...  ...The information is plotted on a Custom Roll Cage Worksheet and then plugged into the computer, which creates a CNC-bender program that's used to produce each tube with the exact lengths, angles, and degrees of rotation.  This is the Custom Roll Cage...  This is the Custom Roll Cage Worksheet, which can be found on the Chris Alston's Chassisworks Web site, www.cachassisworks.com. Information on how to make the 13 51/48-inch half-circle templates and where to place them for main hoop and 'cage-side measurements, as well as where to measure your 'Stang to determine how far apart the 'cage sides should be positioned (front-view measurements) is covered on this worksheet. Once the document is completed, fax it in and the experts at Chassisworks will set you up with a rollcage kit that fits.  This Eaton Leonard computer-controlled...  This Eaton Leonard computer-controlled bender can snap off rollcage tubes of any length and with any degree of rotation or angle in a matter of seconds. Chassisworks is the only U.S. company manufacturing chassis components that has one of these machines.  Scott trial-fits the main...  Scott trial-fits the main hoop to check it for proper width and headliner clearance. The main hoop and every other bar of the rollcage should initially be tack-welded into place. Installing a rollcage involves an extensive amount of positioning and sometimes trimming or modifying bars, so it's important to check and recheck things before making the final-weld commitment...  ...We also kept the headliner,...  ...We also kept the headliner, rear interior panels, and rear seat in place during the fitment process to ensure that clearances and installation locations will be perfect when the 'cage is completely welded down.  Maintaining the removable...  Maintaining the removable T-tops is an important part of this project. Our measurements are perfect, as we're able to operate the latch handles on both sides and install and remove the tops without interference by either 'cage side.  Positioning the driver's removable...  Positioning the driver's removable side bar is critical. NHRA rules require the bar to pass diagonally across the driver's left shoulder, above the elbow, from the main hoop to the floorpan.  This photo shows how, depending...  This photo shows how, depending on where it's positioned, the side bar can impede on the driver when the armrest is in place. Chris Alston doesn't recommend installing side bars so close to the driver, and we agree. We did away with the armrests and moved the side bar outward to allow more room for the driver's left leg, thigh, and arm. We'll address the inside pull handles for the doors when we dive into rebuilding the car's interior.  The H-brace is a Chassisworks...  The H-brace is a Chassisworks original concept for T-top cars and it supports the center area of the roof structure. Scott mocks up an H-brace tube and scribes the windshield brace and main hoop with marks for its mounting location, along with the tube itself, so he'll know where it must be cut for a perfect fit.  Since we want to have a rear...  Since we want to have a rear seat that theoretically can hold at least one passenger-OK, maybe only small children or adults who are as flexible as Gumby can fit back there-Scott positioned the rear bars as far to the sides of the Mustang as possible. In this photo, Steve lands the end of one of the bent rear struts. In a coupe, it's important to carefully place the rear struts to ensure they do not conflict with the tension rods for the trunk lid. Compromise those rods, and you might end up with a trunk lid that will require a piece of 2x4 to keep it propped open.  Before welding inside the...  Before welding inside the car, Steve cuts and positions cardboard pieces to protect the glass from weld spatter-we thought that protecting the windshield was debatable since it was already cracked in two places...  ...The headliner is shielded...  ...The headliner is shielded by a combination of cardboard that's been soaked in water and sheetmetal panels. The rear interior panels and rear seat also are taken out of the coupe at this time.  Scott final-welds the rollcage...  Scott final-welds the rollcage in our project T-top coupe. Before any final-welding is done, the tack welds for the entire 'cage structure are broken and the 'cage main hoop and windshield brace/'cage sides combination are shifted slightly so that Scott can weld in the areas that aren't accessible with the 'cage in its final position...  ...Once the hard-to-reach...  ...Once the hard-to-reach areas have been secured with a solid weld, the bars are put back in their final positions and welded down.  Chassisworks' Pro-Street rollcage...  Chassisworks' Pro-Street rollcage includes a 111/44-inch-diameter permanent back brace, but a removable piece is optional (the removable back brace is not NHRA legal). The back brace installs between the span of the main hoop and is in place to support the front seatback. NHRA rules require the back brace to be positioned at a level that's within 4 inches from the top of the seat.
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