Mustang Dirt Modified - Project Mini Stock

The comment that sparked our inspiration was innocent enough: "We should do that sometime." The conversation was about building a race car and going from being fans in the stands to racers on the track. It still surprises me how little planning we did before committing ourselves to this project. Little did we know what we were in for. There were three of us: brothers Rodney and Scott Helms and I. We knew we wanted to start in a smaller car and race on dirt; but otherwise, our enthusiasm far outstripped our knowledge. It wouldn't be the last time this was the case.

A few of the decisions were easy to make. We chose Lancaster (South Carolina) Speedway because it's close to home, dirt, and offers a division to our liking: the Modified Fours. Mod-4 cars, as they are commonly called, are four-cylinder rear-wheel drivers. They are entry-level, but a cut above the Bomber Class and require a good amount of preparation. That was fine with us since the allure was building a car as well as racing it.

With that out of the way, it was time for step one: Find a car. Here, we ran headlong into our first obstacle. A quick tour through a couple of local junkyards left us overwhelmed. Ninety percent of the field in this class is made up of Mustangs, so that's probably a safe bet, but what model? How much damage to the donor is too much? How much should we expect to pay? We needed help.

Calling All Experts
LWP Auto Salvage is a family-owned scrapyard in Concord, North Carolina, that specializes in helping racers, so we went there armed with plenty of questions. "Most people these days in the four-cylinder classes are racing the Fox-body Mustangs, even though they have a (MacPherson) strut front suspension," explains Wayne Pendergrass, the "W" in LWP and a racer himself. "A double A-arm setup is easier to adjust, but to get a Ford with that you have to go back to the Pintos and Mustang IIs, and those are getting pretty rare." That is a favorite front suspension of the street rod building crowd, too.

Wayne spoke the truth-unmangled Pintos and Mustang IIs were tough to locate, and believe me, we tried. But he did point us to an '89 sedan body he'd already hulled out. We snatched it up quicker than you can say, "Will you take a check?" and Wayne even threw in a pair of doors, a hood and a nosepiece (although it may be damaged beyond repair). By the way, if you don't have a good pair of gloves, get some before you set foot in a junkyard. We invested in several pairs of Mechanix Wear gloves and have been very happy with them. Your hands will still be useful after you root around bent metal.

A hulled-out body may save us time stripping the car, but it also meant we had more junkyard shopping to do. We found both a front suspension and rear end off a '93 model at Love Auto Parts. Again, we weren't just looking for parts; we were looking for someone who could steer us in the right direction, and we found him in Mike Honeycutt. Mike has worked with race teams big and small and knew exactly what we needed. He led us to a '93 Mustang with only minor damage and even took off the parts we needed. Because most Fords, including Fox-body Mustangs, are unibodies (instead of a full-frame car with a body mounted on it) the entire front suspension came off in one piece.

"This car had the nose pushed up. It looks like it hit a ditch or something," Mike said of our donor car. "This is exactly what you are looking for if you need parts or an entire frame, because everything from the front shock towers back is still straight. If you are looking at a car that's wrecked in the side, if the damage is up high you are probably OK. If the damage is down low, be careful because the frame could be bent. If the frame is bent you'll probably never get everything straightened back out right."

Back home in our makeshift shop we were on a roll. We saw the makings of a stout, full-on race car-but our wives only saw a pile of scrap metal. "That's your race car?" was the incredulous response all three gave. Just like that, our spark of inspiration became a bonfire of machismo-laden determination. "That's the perfect foundation for a great race car," we said. "Just wait, you'll see."

Ready, Set, Cut
The rearend and front suspension bolted up with almost no problems. There is still a lot of work to be done in both areas, but the first task was to cut everything expendable out of the car to get the rollcage in there. Even though the major pieces had already been removed, there were still plenty of random bolts, brake lines, and other odds and ends to get rid of. Then it was time to start cutting everything that wasn't absolutely vital.

Caution was the word of the day here. We definitely didn't want to weaken the car or make it unsafe with random cutting. We're likely to do things to the car along the way that neither nature nor any Ford engineer alive ever intended. Safety is one area where we will take no chances.

Unibody cars do not have a full ladder-type chassis but use all of the frame and body to provide rigidity. The rollcage in our race car will do that job, so we cut out everything but the floorpan, firewall (both required by the rules), framerails, and suspension mounting points. Before you get out your cutting tools, remember to cut small so you don't accidentally take out a needed bracket hidden underneath. We were lucky enough to get our hands on a plasma cutter, a wonderful tool that cuts metal cleanly and almost effortlessly with an electrical current and a stream of air. To work properly, though, the head of the cutter must touch clean metal. We also found that an electrical reciprocating saw worked well, especially where anti-vibration matting is glued down.

I'm sure anti-vibration matting is important for passenger cars, but it quickly became the bane of our little operation. Glued in place, the stuff is too well-seated to pull off, too tough to scrub off with a wire brush, clogs an abrasive disc if you try to grind it off, and releases an acrid smoke if you take a torch to it. Because a plasma cutter doesn't cut through the matting well, we took a blowtorch and a scraper to much of it before finally giving up and going with the saw.

One novel approach recommended to us to remove this evil stuff is to buy about 30 pounds of dry ice nuggets and dump them on the floorpan. After the dry ice evaporates, and chills the tar-like goo into a glass-like solid, you strike it with a hammer and it shatters into pieces that a shop-vac can remove. When we get wheels and tires on the car, we'll roll it out of the shop and try this tip. Meanwhile, we'll be writing the blue oval guys requesting that their engineers be a little more willing to put up with the occasional squeak and rattle.

Next: Installing the rollcage.

Lock'er Up
We wanted to lock the rearend of our Mustang, but a locker isn't available for Ford's 7.5-inch rear. A locked rearend applies power through both wheels; there is no differential action. The low-buck solution is to weld the spider gears together so, when we had the rearend apart for inspection, we decided to take the gears to Jim Cook Race Cars to have that done. It's actually a simple process and most racers can probably do it in their own shop.

"All you need is a wire welder and plenty of brake cleaner," Jim says. "You can do it with a stick welder, but it's not as precise and a wire welder just penetrates better." Step one is to thoroughly clean the gears with brake cleaner. The entire operation can be done with the gears still inside the housing, but we removed ours to show the process better. To keep all the weld splatter from sticking to the ring gear or any other critical surface, coat everything liberally with anti-splatter spray. This makes the process of cleanup a snap after you've completed your task.

"You really want to put some good heat to the gears to make sure the weld penetrates and everything holds when you start stressing it," Jim explains. "Turn the welder up like you are welding 11/44-inch to 31/48-inch thick material." Jim starts by welding the top and bottom gear on one side to hold everything in place, then switches to the other side to weld all four gears before returning to weld the last two. Finally, remember that you are welding steel to cast iron, so let everything cool down slowly. Using water or air to cool the piece too quickly, will likely develop cracks in your brand-new weld.