After running into Randy Terwilliger with his ’02 Cooper S for several years at numerous events, we finally arranged a photo shoot with the man and his Mini in the LA canyons.
The 61 year-old tuner was able to get his hands on one of the first US-bound Cooper S, which later became an R&D tool for his company and hobby, M7 Tuning.
Eventually taking the Cooper S to the racetrack and even a wind tunnel, the guys started developing a range of performance parts in 2003. These now include items like a sequential shifter system, which controls gear selection in the stock six-speed transmission with paddles or a bumpstick, and incorporates an LED gear display and a clutch.
As you’d expect, the sequential system provides lightning gear selection. However, it also allows you to stack gears. “For example,” Randy explained, “you’re in fifth gear, coming into a third gear corner. Simply disengage the clutch, use the paddles or bumpstick to go down two gears, then engage the clutch and the computer in the back commands solenoids to select the chosen gear in 400 milliseconds.” The system provides sequential shifting for the stock transmission and is thrilling in the canyons!
Randy and partner Peter Horvath at M7 also designed parts like their 16% supercharger reduction pulley that allows boost to start earlier and climb higher than stock. It’s combined with a 2% larger crank pulley that’s lighter to increase throttle response.
The intercooler and hood scoop on Randy’s car were designed to channel air more efficiently through the intercooler, exiting from an extraction vent on the hood – a solution that’s since been patented by the company.
They also used 400cc injectors and a 65/62mm throttle body. The extra power is then tempered by an Alky Control that triggers methanol injection at 8psi boost to keep intake temperatures consistent, avoiding detonation.
Steve’s Auto Clinic in North Hills, CA provided Randy with a shop to help with the heavy stuff. “If it’s not at M7, it’s being worked on at Steve’s,” Randy said.
Steve’s shop fitted a Quaife LSD, ported and polished both the head and supercharger, installed a Schrick cam and a Jackson Racing header before Vitesse Pro tuned the ECU with Dimsport software.
In total, the engine modifications amount to 230hp at the wheels and 190 lb-ft of torque on the LAPD dyno in Chatsworth, CA. Of course, this doesn’t include the meth or nitrous systems that kicks in at full throttle for extra punch!
Randy’s Mini is littered with R&D parts, and the exterior was no exception. The foglights were replaced with brake ducts, for example. They cool the bigger Ireland Engineering rotors, and the hot air is extracted by the vented fiberglass front fenders.
He admits the fenders are a nightmare to fit because the fiberglass is thicker than the stock metal fenders and paint doesn’t take as well, but the ducts and vents significantly reduced fade.
Tucked under these fenders are Superlite wheels which, after three years of cleaning, Randy powdercoated in black chrome to hide the brake dust.
Working with a customer’s racecar, M7 was invited to test its Mini in a wind tunnel at Sneed’s Speed Shop, Pfafftown, NC. Measurements showed the front splitter produced 154 lb of downforce at 110mph. To match it at the rear, they created a replica of the Mini Challenge Series wing, which gave them 129 lb.
Randy then took his Cooper to the “big” track at Willow Springs in Rosamond, CA and discovered the suspension was on the bumpstops through the faster turns. Back to the drawing board, they created custom-valved M7 coilovers.
Adding SAC adjustable front camber plates and billet adjustable lower rear arms, they also replaced the sway bars with H-Sport parts. With these parts, lap times improved once the camber was set to -3˚ front, -2˚ rear for the track (-1.5˚ for the street).
For its constant track use, the cabin is fitted with NRG carbon fiber race seats and G-Force five-point harnesses. It also has an Autopower roll-bar and a Hot Lap onboard lap timer. The auxiliary gauges monitor everything from boost to air/fuel, water temp and volts. The carbon rear-seat delete houses trick parts such as the sequential solenoid box, methanol reservoir, nitrous bottle and a 12" Earthquake sub.
The latter is a throwback to the car’s previous life on the show circuit, which also included an Eclipse AV8022 head unit, Dension 40GB hard drive and Diamond Audio speakers.
With its dual-purpose build, the amount of custom-built parts on this Cooper S is surprising. From the direct-flow intercooler to the rear wing and sequential shifting, Randy has built an incredible car. Perhaps it’s a good thing we didn’t shoot it a few years ago before much of this development had happened.
et Tech Spec
2002 Mini Cooper S
Owner: Randy Terwilliger
Location: Northridge, CA
Occupation: set lighting tech
Engine: 1.6-liter four-cylinder 16v with Vitesse Pro software, Schrick cams, M7 16% supercharger pulley, 2% lightweight crank pulley, 400cc injectors, Jackson Racing headers, 2.75" straight-pipe exhaust with Borla resonator and Magnaflow muffler, M7 oil catch can, 65/62mm throttle body, AGS intake system, DFIC intercooler, Alky Control methanol injection, Venom nitrous system, TSW motor damper, Aerogel insulation
Drivetrain: stock Getrag six-speed manual transmission with M7 sequential system with paddle and bumpstick shifting, 14.5 lb flywheel, Quaife LSD
Brakes: Ireland Engineering Big Brake kit with 13" front, 11" rear rotors, spaced stock calipers painted red, Ferodo 2500 pads, ARP stud set, Goodridge lines
Suspension: M7 custom-valved coilovers, solid upper motor mount, under-strut system, front and rear strut tower braces, SAC adjustable front camber plates, adjustable billet lower rear arms, H-sport sway bars
Wheels & Tires: 17x8" Superlite L black-chrome wheels with 215/45 R17 Falken Azenis RT615 tires
Exterior: M7 carbon fiber front splitter, rear wing and rear diffuser, M7 Ultimate five-piece grille set, front ducts, DFIC hood scoop and extractor vent, vented side skirts, PIAA 540 driving lights
Interior: NRG carbon fiber seats, G-Force 3" cam-lock five-point harnesses, carbon fiber trim, Autopower roll-bar, polished aluminum nitrous tank and e-brake, Cal Street stainless bottle holder, Momo steering wheel on quick-release hub with paddle shifters, Hamman pedal set, custom shifter and knob, LCD gear indicator, Auto Meter boost, oil pressure, water temp and volt gauges, PLX air/ fuel meter, Hot Lap timer, G-Tech Pro, ScanGauge 2, carbon rear-seat delete, Simpson fire extinguisher
Audio/Visual: Eclipse AV8022 head unit, Dension 40GB hard drive, Navteq GPS, Diamond Audio Hex mids and dome tweeters, Rockford Fosgate amp, 12" earthquake sub, K40 radar jammer, Valentine 1, Dynamat, relocated lightweight battery
Thanks: Leila, Peter at M7 Tuning, Steve, Carlos, Gabriel, Junior and Manny at Steve’s Auto Clinic, TWCompetition