Justin Fivella
June 19, 2013

A lot goes through your mind as you near the end of the quarter-mile with your expensive motor howling at redline. "What's my air/fuel ratio?" "How much boost am I making?" "How high is the engine revving?"

Such thoughts entered our minds as we crossed the stripe at Sacramento Raceway in our newly built smog-legal coupe. Sadly, we had no answers. Why? Because we had nothing more than factory Ford gauges—and that's a serious problem when you have a new supercharged engine that you want to keep alive.

We're making big power while staying emissions friendly with our smog-legal-coupe project LX, and after an SCT chip tune from Kurgan Motorsports last issue, it made 512 hp and 550 lb-ft on 91-octane pump gas. Those dyno numbers were achieved with a catted X-style mid-pipe and spinning the smog pump, and the stock mechanical fan.

The AEM Wideband Failsafe gauge comes with everything needed to monitor boost/vacuum, the air/fuel ratio, and even has a failsafe feature that can save your motor should it lean out.

We also paid a visit to Sacramento Raceway, but a worn differential made traction nonexistent in the lower gears, and the old T5 and stock axles prevented hard launches. While we managed to break into the 11s with an 11.99 at 121 mph, we hadn't unlocked all the performance.

With that, we paid a visit to Stanton Performance in Martinez, California, and together with owner Jeremy Stanton, we made a list of the coupe's shortcomings that quickly grew from an inch to a mile. Its drivetrain and suspension flaws were glaring, but before diving into the chassis, there were smaller mods that should net huge improvements.

Protecting The Investment

Lets be honest, driving a forced-induction car without quality gauges is like playing Russian roulette. Monitoring engine vitals is crucial since a tuned motor can grenade in a heartbeat if a lean condition occurs. Although there's big business under the hood of our coupe, we didn't want the rest of the car to snitch off what lies beneath. Why, because there's nothing cooler than a sleeper. So we decided to install AEM Electronics combination boost and wideband gauge. But when we also discovered the high-tech gauge had a failsafe feature, we struck gold.

"Our Wideband Failsafe gauge comes with a built-in failsafe feature that can be programmed to activate various things that can save a motor when the AFR moves outside a preset window," said Lawson Molica of AEM. "If the AFR reaches outside the safe zone (lean or rich), the failsafe can be set to trigger something as simple as a check-engine and shift light, or if you prefer something more concrete, it can be set to pull ignition timing or open the wastegate on a forced-induction application."

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Chew on that for a second. For those who prefer a soft slap on the wrist, the failsafe can be set to illuminate your Check Engine light that will remind you to chop throttle. The failsafe can also open a wastegate to bleed boost, activate an alternative fuel map, cut the ignition coil, or even trigger the ECU or an MSD to pull timing.

The included AEM software is simple and the failsafe feature is highly adjustable. Users can set the length of time the a/f ratio is allowed outside the safe limits before registering the failsafe. You can prevent false triggers from spikes by programming a time delay. With the delay, the failsafe is only activated after the set a/f ratio has exceeded the safe boundaries for a set amount of time. The failsafe can also be activated based on a/f ratio against vacuum or boost. Monitoring the tune in relation to boost or vacuum helps prevent false triggers during city driving where on/off throttle applications can cause significant a/f changes.

"The software allows the user to set a wide a/f window at low vacuum or boost levels where a/f ratios aren't as important (say from 15.0:1 to 9.0:1) and then tighten the zones at which the failsafe will be triggered (say, 11.0:1 to 12.5:1) where it's most important, as the revs or boost rise," Molica said. (See 5 for an illustration that further explains this feature.)

If the capabilities of the failsafe feature aren't enough, the gauges can also store up to three hours of onboard data-logging memory at 25-hertz per second, and can also be connected to a stand-alone computer for greater capabilities. It's also affordable at $316.35, and looks damn cool with its LED perimeter ring and full-color Organic Light Emitting Diode inner screen. The gauge comes with multiple face-plate covers and can be configured in dozens of combinations. Want your info in the middle screen and the boost to rise around the edges with the LEDs? Sure. Or maybe you want boost or a/f ratio solely displayed on both screens. You can have that too—it's all user-selectable.

We inconspicuously housed them in the center stack with a gauge plate from Latemodel Restoration. This quality aluminum panel retains the radio slot, while adding a spot for three gauges. Speaking of multiple gauges, since our coupe has dual exhaust, we opted for two AEM gauges, one for each bank of cylinders. Those with a Y-pipe or single setup can get away with a sole gauge, but we wanted the utmost protection.

As for the actual execution of our failsafe feature, we decided that pulling timing during a lean condition was the best method of protection. Since the Vortech V-3 Si super- charger kit came with an MSD 6 BTM, we opted to also use the MSD 8982 Timing Control Unit to pull timing on command. The 8982 is a nifty add-on that not only allows the timing to be retarded during cranking to help fire-off a high-compression motor, but it also has a single-stage, high-rpm timing activation that can be used to pull timing for nitrous applications, to preserve a race motor against rising combustion temps or in our case, to pull timing if the failsafe triggers it. The $179.95 unit comes with chips to retard the timing from 0 to 4 degrees, but we opted for an additional package with 0-to-10-degree chips.

After careful consideration, we decided 10 degrees of timing retard would be sufficient to save the motor under a lean condition, as anything less and we'd be leaving too much on the table; anything more, and it could result in too drastic of a power cut (imagine if that happened mid-corner on a road course). During a failsafe test, we noted that 10 degrees of retard was immediately felt from the driver's seat, reminding us to instantly cut throttle. As for the desired a/f range, we dialed the failsafe to trigger at 12:5.1 on the lean end and 10.0:1 on the rich side. This left a window wide enough to prevent false alarms, while also leaving enough wiggle room on the lean side to chop throttle before nuking a piston.

No More Miss-Shifts

The factory Fox-body tachometer has proven to be anything but accurate under full throttle. It might correctly reference to a timing light at steady throttle, but under acceleration the stock tachs can be severely inaccurate. Despite seeing redline on the tach, you may actually be shifting several hundred-rpm shy. In both cases, you're leaving e.t. on the table since you're either banging the limiter or short-shifting.

7. The MSD 8982 Timing Control Module is an affordable unit that can retard timing during start-up to help high-compression motors and also has a single stage of high-rpm timing retard. This is especially handy for nitrous cars, for pulling timing on the big end to preserve a race motor, or in our case, pulling timing if the failsafe is triggered.

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14. Part of the Flex-a-lite’s success is the variable speed controller that can be set to keep the car within a certain temperature range. The fans will kick on at 60-percent and gradually increase to 100-percent to keep the coolant temps in the given window. This prevents the sudden load most fans place on the charging system when they kick on full power.

We chose to preserve our LX's sleeper status and mount a quality shift light. No big-face tach here—just a small digital LED shift light from MSD. The lightweight unit (PN 8963) has six LEDs and can be mounted in a variety of locations. For now it's on the column, but eventually we'll hide it in an air vent for ultimate sleeper status.

The digital shift light is easy to mount, compatible with almost any engine and can be programmed with multiple set points (in case your shift points vary per gear). The intensity of the LEDs is adjustable and the side-mounted LED screen makes setting such shift points a breeze.

The digital gauge is a cinch to install and proved we'd been previously short-shifting far below our intended redline. In fact, 6,000 rpm on the shift light displays as 6,600 on the inaccurate factory tach. That means we were severely short-shifting because 6,000 rpm (our intended shift point) on the tach was actually 5,400 rpm, which meant we were giving up precious time at the track. For a mere $178.60, we consider it a cheap investment.

More Power and Cooler Temps

Lets be honest, while the stock mechanical fan does an admirable job of keeping down coolant temps, it also saps power and sounds horrible as it whirls away. With our hefty dual-core highway patrol radiator and a new 180-degree thermostat in place, overheating was not an issue, but we wanted a cleaner look and max power from the stroker. A call to Flex-a-lite narrowed our search for the perfect electric fan.

Our coupe proved to be a difficult patient because the Vortech supercharger robbed precious underhood space. Between the V-3 Si head unit and the supplied crank pulley protruding into the areas commonly used for aftermarket aluminum radiators and electric fans, we had little room. Flex-a-lite stepped in with an ultra-slim, dual-electric fan setup that moved serious air.

Although we could've opted for a pusher fan in front of the radiator, generally puller fans mounted aft of the core are more efficient. Thankfully, the Flex-a-lite (PN 410) is a lithe 25⁄8-inch thick and easily slides between the blower and the large highway-patrol radiator. As anyone with a blown Fox will tell you, freeing up real estate is a blessing. Now we have better access to the belts and can make tension adjustments without having to remove the upper radiator hose.

Small additions oftentimes make the biggest improvements.

A pair of 12.125-inch, eight-blade fans move a combined 2,500 cfm, which is more than enough for our motor, even on the hottest of days. Flex-a-lite offers several different fan control modules, but we chose the variable-speed controller for its extreme versatility.

Unlike traditional controllers that kick the fans on 100-percent at a set temperature, the variable speed unit can be set to activate within a set temperature window. This means instead of suddenly bringing the charging system under a huge draw, the fans can be set to run at 60-percent capacity at a certain temperature and increase in speed until reaching 100-percent as the water temp rises. In many incidents, the fans will never reach 100-percent because traffic clears and you're able to move, or the given fan speed is enough to cool the car. It's a clever method of lessening the load on the charging system.

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If there's one thing Flex-a-lite prides itself on, it's the completeness of the kits. The (PN 410) kit comes with everything needed to push mondo air. In addition to the dual fans, shroud, and weatherstripping, it also comes with the aforementioned variable-speed box, along with all the mounting, wiring, and temperature-sending pieces.

To prove its worth, we hit the dyno at Advanced Engine Development (AED) in Shingle Springs, California. AED is one of the premiere Mustang performance shops on the West Coast, and has extensive knowledge of Blue Oval pushrod and mod motors. Owners Shaun Perry and Drew Wallace build some of the fastest Mustangs on the West Coast, and even offer some incredible custom mail-order tunes for the Coyote-powered Mustangs. Suffice it to say, our coupe was in good hands.

Much to our surprise, the electric fans freed up more power than we anticipated, 11 hp and 22 lb-ft of torque to be exact. Peak gains were impressive and broad, as bottom-end and midrange portions of the powerband showed over 10hp and 20 lb-ft improvement from 2,000 rpm to redline. Lets also not forget the fact an on/off switch can be hardwired to cool underhood temps while sitting in the staging lanes. As we all know, cooler temps mean more power.

While this month's mods weren't big-ticket items, it's proof that small additions oftentimes make the biggest improvements. Now with an accurate eye on our coupe's vitals, backed by an engine-saving failsafe and a slick set of electric fans, it's time to dive underneath our Smog-Legal Killer and build the drivetrain and suspension to match the mighty motor.