You know the feeling, running into an old flame after she’s put on 50 pounds in the years since you broke up. As you struggle with feeling fortunate and like a superficial slimeball all at the same time, you realize that sometimes timing really is everything. For muscle car buffs, the same goes for the tumultuous years leading up to the smog era, especially if Mustangs are your thing. Everything was cool until 1970, but even Mustang diehards despise the bloated proportions and disfigured mugs of the ’71-73 models, disparagingly labeling them “Clydesdales” for all eternity. With Mustangs of this vintage, Mach 1 more aptly describes the speed at which mortified onlookers ran from them rather than their go-fast potential. The bottom line is that if you were going to buy a Mustang in the ’70s, then 1970 was a good year to do it. And if you’re fortunate enough to have scored the last of the good-looking vintage Mustangs—regardless of whether it’s a coupe or a fastback—it’s your civic hot rodding duty to uphold the Mustang legacy by transforming it into a badass street machine.
At just 16 years of age, Colby Henton was ready to answer the call. Granted, the year was 1990, and he had the advantage of critiquing the Mustang lineage through retrospective eyes, Colby set the cutoff point at the ’70 model year while searching for his first car. Ever since he was a kid, he knew his first car had to be a Mustang, as Ford’s ponycar runs deep in the Henton household. Colby vividly recalls his uncle, grandfather, and grandmother each owning Mustangs during his childhood, and dad was a Blue Oval-or-bust man as well. “I’ve always liked the ’70 body style because I think the early coupes don’t look that aggressive, and the ’71-and-later Mustangs got too big and strayed from the muscle car formula too much,” he says.
Colby got a job at Dairy Queen one summer, and started shopping for his first car once he saved up some money. He found the perfect target when he ran across a nicely restored ’70 Mustang that still had the original 302 small-block. “I didn’t have enough cash to buy it, so I talked my dad into cosigning a $2,500 bank loan for me. He went out and bought the car a week later without telling me about it, so it was a total surprise,” he says. “One day while I was in school, he left the car in the student parking lot, and dropped off the keys in the office for me with a note attached to it. I didn’t know what it was at first, but then I saw a horse on the key ring and figured it out. It was one of the best days of my life. I drove the car all afternoon and took the long way home.”
The Mustang has been kept...
The Mustang has been kept in the garage for the last 20 years, and it shows. Early on in the build, Colby got hurt in an ATV accident and could no longer work on the car. He hired Doug Leopold of Classic Collision and Restoration (Bryan, Texas) to finish the build. The scoop was added by the car’s original owner to cover up a dent.
With the limited resources of a teenager’s budget, Colby kept the car mostly stock throughout high school. He bolted on as many engine mods as his budget allowed, and engaged in some street skirmishes here and there. Then in 1997, Colby hit the dragstrip and got hooked. Since the stock motor was getting tired, he dropped in a fresh 302 and a set of 4.11:1 gears, and sprayed the Mustang to 7.14-second passes in the eighth-mile. That’s equivalent to a deep 11-second pass in the quarter-mile, which was pretty darn quick for the era. Unfortunately, Colby got a little too greedy with the nitrous pills, and like many Mustang racers before him, he split the delicate factory block in half. After that episode, Colby started messing around with trucks and the Mustang sat for the next six years.
As the Mustang languished in his garage, Colby was busy boosting several Powerstroke diesel rigs into oblivion. Next came an ’02 Lightning pickup, but despite its blown and squeezed goodness, the Mustang beckoned for attention. Consequently, Colby put the truck phase behind him in 2006 by selling the Lightning, and shifted his focus to the Mustang once again. His goal was to resurrect his car in the g-Machine tradition with driveability as a top priority. Likewise, he was more interested in passing away the miles in comfort rather than wiping it down incessantly. “I wanted to build a car that I could hop in, turn the key, and drive anywhere in comfort. The last thing I wanted was a car I had to work on or clean all the time,” he says.
Like the rest of the car,...
Like the rest of the car, black, gray, and silver hues create an understated feel under the hood. With a 4150-style throttle body, it takes a keen eye to spot the FAST EFI system in the first place. Colby wanted to keep the original hood, so he adapted a blow-through carb hat to fit the throttle body in lieu of a traditional air cleaner.
There are certainly different degrees of how much each Pro Touring build swings the pendulum toward modern trends and technology, and Colby didn’t want to go over the top. As such, he opted for Windsor power instead of the more fashionable mod motor option. The venerable 351W architecture lends itself to lots of easy cubic inches, so Colby started out with a production block, bored it 0.030 over, then dropped in a 4.170-inch steel crankshaft. Matched with 6.200-inch connecting rods and forged 10.0:1 pistons, the result is a cool 425 cubes. The air supply comes from ported 225cc Trick Flow aluminum cylinder heads, and an Edelbrock Victor single-plane intake manifold. A Crower 234/246-at-.050 hydraulic roller camshaft actuates the valves, and exhaust exits through custom 1.75-inch headers and dual Pypes 2.5-inch mufflers.
The simple-yet-effective combo is good for 409 hp and 439 lb-ft of torque at the rear wheels. Backing up the stout 425 mill is a Tremec TKO five-speed manual trans. “I have fond memories of how this car used to sound with a cammed-up 302, and I thought that going with a mod motor would take away from that. Small-block Windsor motors have a unique sound to them that the newer motors don’t have,” Colby says. “I also liked the idea that 351Ws were available from the factory in these cars. Even though I wanted an old-school motor for the sake of nostalgia and sound, I decided to go with a FAST XFI fuel-injection system for driveability and reliability. The sound and feel of an old-school motor and the reliability of EFI is the best of both worlds.”
The foundation of any Pro Touring build is the chassis, and unlike in the engine bay, none of the wobbly factory bits were spared in the name of nostalgia. Up front, the stock underpinnings were replaced with a Heidts crossmember assembly, control arms, and spindles. Out back is a Chassisworks four-link that swings a fabricated 9-inch rearend. Providing an excellent balance of handling and ride quality are RideTech air springs and shocks at each corner. The stick comes from BFGoodrich KDWs wrapped around 18-inch Billet Specialties Patriot wheels, and four-piston Wilwood calipers bite down on 12-inch rotors at each corner. To say that the modern hardware has paid dividends would be a massive understatement. “Everything I’ve done to this car has been to improve driveability. Between the fuel-injected motor and the suspension upgrades, the difference in handling and streetability compared to the stock setup is night and day,” Colby says. “The car has tons of power, drives much more smoothly, and I can go anywhere in it. There’s nothing like cruising in it with the exhaust rumbling, A/C blowing, and radio jamming.”
The superclean undercarriage...
The superclean undercarriage looks the part of a car that never gets driven, but that’s simply not the case. Don’t let the polished exhaust fool you. The entire suspension has been powdercoated, and the undercarriage is covered in bedliner material to help shed water and keep maintenance to a minimum.
In addition to enhancing performance and driveability, show-quality aesthetics were part of the grand plan all along. Even though extensive sheetmetal mods are becoming more commonplace in the walk of g-Machines, Colby wanted to keep things simple. Other than fixing a small patch of rust in the floorpan, smoothing out the firewall, and filling in holes in the engine compartment and undercarriage, the body is mostly stock. Instead, the mean stance, aggressive factory body lines, and Volkswagen Reflex Silver paint do all the talking. “I like the way these cars look from the factory, so I didn’t want to change the body much at all. Lots of people like to shave the driprails and door handles, but I didn’t want to take away from the car’s original profile.”
As subjective as a car’s styling might be, few people would disagree that the ’70 Mustang is a far better looking machine than the Clydesdales. And let’s not even get into the Mustang II debacle. With the last of the aesthetically pleasing old-school Mustangs at his disposal, Colby has met his duty of turning it into a sweet street machine that can do it all. Even so, there will still be those who question putting so much effort into any Mustang that isn’t a fastback. “I know that it doesn’t make that much sense to put a lot of money into a Mustang coupe because there just isn’t that much demand for them,” he admits. “However, I didn’t build my car to sell it. I got to build my first car like I always dreamed of building it, and not many people can say that.”
Colby prefers driving over...
Colby prefers driving over polishing. He had the wheels ceramic coated to give them a nice sheen that wouldn’t require constant cleaning.
“I wanted to build a muscle car that drives and handles as well as a new car. I think I’ve accomplished that.” —Colby Henton
Type: Ford 425ci small-block
Block: factory 351W bored to 4.030 inches
Oiling: Melling pump, stock pan
Rotating assembly: Coast High Performance 4.170-inch forged crankshaft, 6.200-inch steel rods, and 10.0:1 pistons
Cylinder heads: Trick Flow 225cc aluminum castings with 2.080/1.600-inch valves ported to flow 330 cfm
Camshaft: Crower 234/246-at-.050 hydraulic roller; .550/.573-inch lift; 112-degree lobe separation angle
Valvetrain: Crane lifters, timing set, valvesprings, and 1.6:1 rocker arms
Induction: Edelbrock Victor intake manifold converted to EFI, FAST throttle-body
Fuel system: FAST XFI stand-alone computer and 30-lb/hr injectors; Walbro in-tank pump, Aeromotive rails
Ignition: FAST crank trigger, MSD 6AL ignition box, Taylor plug wires, factory Ford coil pack
Exhaust: custom 1.75-inch stainless steel headers and 2.5-inch X-pipe, dual Pypes mufflers
Cooling system: Edelbrock water pump, Griffin radiator, SPAL electric fan
Built by: Coast High Performance
Output: 409 hp and 439 lb-ft at rear wheels
Transmission: Tremec TKO 600 five-speed manual; Modern Driveline flywheel and clutch
Rear axle: Chassisworks 9-inch rearend with 3.89:1 gears, Strange 31-spline axles, and limited-slip differential
Front suspension: Heidts control arms and spindles; RideTech air springs and shocks
Rear suspension: Chassisworks four-link; RideTech air springs and shocks
Brakes: Wilwood 12-inch rotors and four-piston calipers, front and rear
Wheels: Billet Specialties Patriot 18x8, front; 18x10, rear
Tires: BFGoodrich KDW 245/40R18, front; 275/40R18, rear