Steve Turner
Former Editor, 5.0 Mustang & Super Fords
December 1, 2007
Here she is in all her modest glory-the Fox 500. Right now, our '88 5.0 LX with T-tops is more Fox than 500, but every project has to begin somewhere. If you've been following along, you know our friends at Paul's High Performance have already stripped the car of its 5.0 engine and T5 transmission ("Supporting Cast," Oct. '07, p. 56). In the coming months, PHP mastermind Paul Svinicki will put together a plan to run the GT 500 engine using the same electronics found in the '07 GT 500, meaning our OG Pony is going to have throttle by wire. Stay tuned, folks-this project's gonna be a wild ride.

Horse Sense: While our rollbar was specifically configured for street-friendly ingress and egress, Maximum has NHRA- and SCCA-legal bolt-in rollbar kits for Fox and SN-95 Mustangs, including convertibles.

If you aren't familiar with the inception of the Fox 500 project, it began innocently enough when Tech Editor KJ Jones sent me an e-mail saying I had to check out this car because it was somewhere near our Florida offices. The car in question was purported to be an '88 5.0 LX hatchback with T-tops. Similar to KJ's rare T-top coupe, I'd never seen one of these cars in the flesh. I'd only seen '87-'88 GTs with the long-discontinued removable roof panels, but never an LX with the T-top. After master Melvin and former 5.0&SF tech editor Mark Houlahan confirmed the car was a legit T-top LX, I bought it on the spot.

The car was far from a clean stocker, but it did appear exceptionally straight. The core support was intact. The floor saw no signs of improper floor jack use, and even the body didn't have much more than a few dings. The car's worst problems included an easily replaced rusty hatch and spot rust where the hatch rubbed the roof. In short, it was the ideal car for me. It was rare, but it was beat up enough that I wouldn't feel too guilty about completely revamping it.

Of course, the idea of restoring it never crossed my mind. Leave it to me to find a rare car and the first thing I can think of is shoving in the most powerful factory Mustang engine created thus far-an '07 Shelby GT 500 crate engine from Ford Racing Performance Parts. I didn't come up with the idea right away, but as I was driving home with my new purchase, I was taken aback by all the squeaks, rattles, and cowl shake coming from my new flexi-flyer. I guess I've spent too much time in more rigid coupes and the rock-solid S197. The car had never worn chassis stiffening of any kind-no strut-tower brace, no subframe connectors, nothing. Adding big power was sure to create more flex if the situation wasn't handled from the get-go.

I have to do things the hard way. I really wanted to keep going with the car's Maximum Motorsports suspension and chassis theme, but the Fox 500 will be driven on the street more than anywhere else. As such, I want to be able to pack up the whole family and hit a cruise night or go for a joy ride. Maximum's rock-solid subframe connectors are part of the plan, but a 'cage would further solidify the car. Maximum has a variety of bolt-in rollcages, but I was looking for something different. First, I wanted a removable crossbar so my son could easily hop in the rear seat. Second, I wanted low door bars to stiffen the chassis, but not make it difficult for grown-ups to slide in.

Fortunately, the crew at Maximum was willing to bend up something special for us, with low door bars that stiffen the car without getting in the way. We employed the basic Maximum four-point bar (PN MMRB-1.3; $285) for Fox hatches. It has a removable harness mount (crossbar) and the new low door bar option (PN MMRBO-LB-1; $120). Owners of street hardtop Foxes can now get the same user-friendly chassis-stiffening as the Fox 500. How cool is that?

We dropped by Paul's High Performance in Jackson, Michigan, en route to the Milan, Michigan, NMRA race to document the installation of our new 'cage by technicians Mike Sears and Karl Roekle. Check it out as we give the Fox 500 a backbone.

We'll be completely revamping the Fox 500's interior, so Mike and Karl gutted it before we arrived, removing the console, carpet, rear seat, plastic trim panels, hatch carpet, and so on. It's not necessary to take out all that stuff-you can work around the interior by pulling back the carpet-but it makes things easier to have plenty of room. One thing you must do is remove the seam sealer from the floorpan to ensure the rollbar mounts seat flat on the floor. A hammer and chisel were Karl and Mike's main tools, but they occasionally employed a heat gun to loosen the ancient sealer.

After bolting in the crossbar and sliding on the rear supports, Mike and Karl rotated the main 'cage into place. The bar fit like a glove, with the rear brace mounts conforming to the rear wheelwells as though it was made for this car. Likewise, the main hoop mounts fit snugly in place.

Mike bolted the rear braces in place to make sure everything was solid before he and Karl began drilling holes in the Fox 500.

Mike and Karl test-fit the low door bars and began drilling the floorpan. Make sure there aren't any brake lines, fuel lines, battery cables, or anything else critical below the mounting holes before you begin drilling.

The floorpan isn't perfectly flat, so it's necessary to crush it with a jack when installing the backing plates, which reinforce the mounts. These flat plates have holes matching those on the rollbar, so they sandwich the floorpan to provide maximum structural rigidity. To further strengthen the car, you can weld the bar in, but bolting it in first ensures it's positioned properly before you bust out the smoke wrench.

With the bolts through the mounting and backing plates, Karl held the nuts in place with a wrench while driving the bolts home with an impact gun. This bar isn't going anywhere unless they unbolt it, which they actually did to send it out for powdercoating after we left.

Just like the main hoop's mounting plates, make sure the rear wheelwells are clear of anything before drilling. Likewise, don't punch the drill bit through the wheelwell and into the rear tire. To be extra safe, jack up the car and unbolt the wheel. This might be necessary if the car is lowered, has large-diameter wheels, or both.

With the main hoop and rear braces bolted in place, Mike and Karl slid on the low door bars. They also ensured the front mounting plates were in their proper spot before drilling through the door bars so they could bolt them to the main hoop.

Finally, Mike and Karl drilled and bolted down the door bars' mounting plates. The passenger side went in without a hitch. Only the driver-side floorpan gave the guys resistance, but after some judicious application of the bottle jack, the mounting and backing plates sync'd up and the 'cage was fully bolted in.

Here's a look at the finshed product. The 'cage conforms nicely to the lines of the car.

With the bolt-in crossbar removed, it will allow easy access for front and rear seat passengers. Better yet, the car sounds more rigid. How can we hear it's better, you ask? Well, Mike did nonscientific, but reassuring, testing for us. Before the 'cage went in, Mike gently knocked on the car's roof panel. The sound was not unlike that of a tin can. Once the 'cage was bolted in, he repeated the knock. The sound was no longer hollow and tinny, but full and solid. Just wait until we weld in those subframe connectors. The Fox 500 will sound and feel like a new car.