The test drive is packed with excitement and some trepidation. You get to actually drive and enjoy the car you’ve been diligently building over the past several months, but at the same time, you need to be keenly aware of what the car is doing. You need to identify any problems, particularly serious engine, transmission, and suspension problems that need to be resolved for your safety and the car’s health. At the same time, you need to become acclimated to driving your new car.
Ease your Cobra out of the garage and make sure that the clutch is engaging and disengaging properly. With our fire-breathing 427-ci stroker mill making a glorious noise even at idle, we glanced at the gauges in the dash and acknowledged that all was well so far. We coasted out of the garage and tested the brakes on the driveway. Thanks to the electronic fuel injection, the Mk4 started up easily. It stops sure, short, and straight.
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When you’re on your first drive, it’s a good idea to stay within a few miles of your home and perhaps rumble around your neighborhood for the first 15 minutes. If you encounter problems, you’re not far away and can be easily rescued. You need to get accustomed to your roadster. Most Cobras have a curb weight of around 2,500 pounds, with powerplants that produce from 300 to 700 hp. This power-to-weight ratio makes these Cobras super cars, so take your time and be careful. You don’t want to mangle your new roadster on your first drive.
As you drive, listen to the engine carefully. Shift through the first three gears and make sure that the transmission is properly selecting the gear and staying in gear. Listen to the rear end; make sure there is no clunking. Feel how the suspension is operating in the corners and over road bumps. It should drive in a straight line, providing smooth yet firm dampening, track predictably through corners, and brake securely.
Check the speedometer, tachometer, fuel gauge, amp meter, and in particular the temperature gauge. Make sure the engine temperature is within the normal operating range. If it’s too hot or cold, you may have a thermostat issue, there might not be enough coolant in the cooling system, or the engine may be losing coolant. Make sure the climate controls, as well as the heater and air conditioning (if equipped), are functioning properly.
After running the car for 15 minutes, pull into a filling station, perform a visual inspection, and check all fluid levels—engine, transmission, power steering, and so forth. Look for anything that appears unusual or out of place. Look under the hood and under the car for leaks. If there are no leaks, proceed to the next phase of the shakedown test.
If you can find a large, wide-open parking lot, such as one at a mall or industrial park, use it with discretion to ascertain the running condition of the car. Away from other cars, check the steering again by cranking the wheel from lock to lock. Accelerate to 40 mph and brake aggressively but do not lock the brakes. You want to bed-in the brake pads, yet not glaze them over, and at the same time verify operation. If everything is in good working order, you can proceed to the freeway.
On the freeway, accelerate hard (but not insanely fast) through the gears, once again listening to the engine, transmission, and differential. At this speed, you need to be sure that the chassis feels solid, the car is tracking straight, and the suspension is performing correctly. There should be no vibration through the steering; no clunking, thumping, or other abnormal sounds from the suspension when encountering expansion cracks, potholes, or road ripples.
If you do encounter steering issues or suspension noise, these may be attributed to an unbalanced tire, a flawed or out-of-round wheel, a faulty ball joint, or other suspension issue. If you quickly identify and remedy the problem, that’s great. But if you need help sorting out the suspension, take the Cobra to a tire service center or alignment shop. A short test drive by a professional will be a great help. As mentioned previously, we’re glad that we had the alignment experts give our chassis a professional and thorough going over before we attempted our first drive.
When all systems are fully functional, it’s time to conquer your favorite road, road course, or quarter-mile.
Our Maiden Voyage
On our maiden voyage, the Mk4 performed like a champ. The QMP Racing Engines Dart aluminum 427- ci stroker mill with the Dart Pro CNC aluminum cylinder heads seems to have endless torque and horsepower. There’s no way we could test the limits of this powerplant on the highways and twisty country roads of America. She’ll need to be exercised on a closed sports car racing circuit someday soon. But for now, the engine produces a lusty idle. It’s loud enough to set-off three car alarms going 15 mph up and down our dual cul-de-sac street once.
To our knowledge, we’ve constructed the only FFR Mk4 roadster that has a Tremec T56 Magnum 6-speed manual transmission. We’re very pleased to say that this bulletproof trans shifts easily and precisely. Having that 6-speed Hurst shifter by our side and the gearbox attached to it, we feel as though we’re piloting a much more current sort of race car than a replica of the world’s fastest production sports car of the 1960s.
The manual rack-and-pinion steering on our FFR requires a little muscle at slow speeds, but the steering is precise and gives great feedback. Likewise with the actuation of the cable clutch pedal; a strong left calf muscle is needed to engage/ disengage that third pedal, as is the application of the brake pedal for the other calf.
I suppose there’s something special about piloting any sort of race car, which is what the original Shelby Cobra 260, 289, and 427SC were. The feeling that I get every single time I drive our Cobra is one of swelling pride and accomplishment. Dad and I have constructed a beast of a car that handles better and is faster than 95 percent of the cars on the road! From a fiberglass body on the chassis, 62 aluminum panels, 22 boxes of parts, another 25 to 30 boxes of engine and transmission components, a pile of money, endless enthusiasm, and perseverance, we crafted a Factory Five Racing Mk4 Cobra roadster replica that offers stunning and reliable performance and is absolutely beautiful to gaze upon or pamper with yet another coat of auto wax.
It seems we do have the Blacksmith gene after all. Perhaps you do, too. You simply need to have a yearning desire to create something with your hands, your brain, your bank account, your spouse’s approval, your unending persistence, and a commitment to excellence.Of course, it also helps that you have this particular book to assist you in your creative endeavor.
Are you ready to take your journey? You’re sure to have mostly triumphs and maybe a few mishaps in your Cobra replica building adventure. When you create the sports car of your dreams, you’ll be doing something that most haven’t done before.
Written by D. Brian Smith and Posted with Permission of CarTechBooks