Lethal Performance boosts its Mustang GT project to 700 horsepower
By Steve Turner
You had to know this time was coming. When Lethal Performance gets its hands on a new Mustang project you know the mods are going to happen in a hurry. When it is a V-8-powered Mustang, you know that a supercharger is on the way, and the odds are it is one of the positive-displacement offerings from Whipple Superchargers.
The Harvey Hutch Himself of Power by the Hour gets down to business by removing the belly pan and front fascia from the Lethal Performance 2015 Mustang GT. There are numerous fasteners of various sizes, so take your time. Be sure you keep the fasteners organized so you can easily reinstall them. The system comes with an expansive manual, so just follow the instructions carefully.
“We run Whipple Superchargers on our cars for many reasons. Most important, though, is the company’s kits make excellent horsepower and torque due to their twin-screw design, delivering instant boost. There’s no waiting for the rpm to rise like the centrifugal blowers require. Just slam the pedal to the floor and you’re making power,†Jared Rosen of Lethal Performance explained. “Over the last 10 years we’ve also created a great relationship with the entire Whipple Supercharger family. They’ve always treated us like family and we feel the same way about them. So, if we’ve got a car that they have a kit for, you can bet we’re putting it on.â€
If you have been living under an engine block and you aren’t familiar with the Whipple superchargers, these units are of the twin-screw variety that compress the air inside the supercharger and feed it into the engine. They are available in a variety of displacements, and as you might expect the bigger blowers deliver even higher levels of boost.
After putting aside the fascia, Harvey removes the cold air intake, throttle body, and intake manifold. Before pulling out the intake, you will need to disengage all the factory connectors, including the fuel rails.
For the 2015 Mustang, Whipple has created a 2.9-liter supercharger based on its W175ax compressor. This unit features a front-feed and an integral bypass valve. If you are familiar with the prior Whipple Mustang systems, you know that they have featured a rear inlet and a front drive, but by moving the inlet to the front and driving the blower at the rear via a jackshaft, allowed Whipple to increase the plenum volume, reduce restriction, and add and additional 1.75 inches of intercooler coverage.
“The new 2015 kit is very impressive. The front-feed design, huge intercooler, massive heat exchanger with optional fans, aluminum intercooler reservoir, and the race-ready belt system are just some of the things that stand out from the previous design,†Jared explained. “The kit comes with everything individually bagged and labeled and includes a full-color installation manual. It’s amazing to see the thought process in designing a kit like this, as well as how many individual pieces it takes to make it complete. Kudos to Whipple for in my opinion its best supercharger kit so far.â€
With the intake removed and the valley clear, you will need to reorient the harness for the knock sensors and tape up the connectors for the Intake Manifold Runner Controls, which will no longer be used with the supercharger system. Do, however, be sure to make sure the connector for the Intake Air Temperature sensor is accessible, as you will need to plug in the supplied extension harness. Here Harvey has cut the heater hose, swapped over the restrictor, and installed the supplied heater hose using heat-shrink clamps.
These changes to the blower kit added up to a more efficient design, which should allow for a greater power production. Moreover, Whipple designed a completely new system for the 2015-and-up Mustang GT (PN WHP-WK-2620B; $8,295). It is a comprehensive and well-designed system that delivers and OEM-level of fit and finish. Better yet, the system includes an even larger heat exchanger—60-percent larger than prior Mustang kit—with the option of adding two SPAL 11-inch fans, which will deliver a constant supply of air over that heat exchanger, which handles 1.3 gallons of coolant.
Of course, what really matters to you is what this system will do for a 2015 Mustang GT. As such, we packed up our cameras and headed to Power by the Hour in Boynton Beach, Florida, to document the installation and testing of the all-new Whipple system for the S550.
“We’re extremely happy with the results of the kit. I remember putting the older 2.9-liter design on our 2011 5.0-liter and making around the 600 rear-wheel horsepower,†Jared said. Now we’re above 700 rear-wheel horsepower, and we haven’t even started turning this thing up yet! I wonder what this thing will do at 20 psi with some E85?â€
Until they make that move, let’s see how you can bolt 700 rear-wheel horsepower onto your new Mustang GT.
Harvey muscles the Whipple lower intake manifold into place after installing the O-ring seals on each runner. You might want a friend to help you with this part so you can make sure there are no wires or hoses under the intake when you seat it. Then torque the fasteners in the pattern prescribed in the instructions, first to 88 in-lb and then to 106 in-lb on the second pass. You can see the intake ships assembled with sensors, fuel injectors, and the Whipple fuel rails. The manifold looks great matched to the wrap on the Lethal GT. Black is the standard finish, but you can for custom colors on the blower and manifold for $600, while polishing both will set you back $800.This stout bracket allows you to add the supercharger driver pulley to the factory six-rib FEAD. Harvey first pressed the support stands into the bracket with a vice, then he bolted on this idler pulleys and the spring-loaded tensioner. The bracket bolts to the timing cover without any modifications. Just torque the 10mm bolt to 25 lb-ft and the 8mm bolts to 18 lb-ft. There is an optional 10-rib system available for those looking to run more boost. It includes an SFI-approved ATI damper.Lethal Performance’s Jared Rosen (right) chipped in to help Harvey set the blower in place. With its spot-on paint match, the 2.9-liter Whipple looks right at home atop the Coyote engine. Be sure the bypass valve is properly seated and that there are no hoses or wires betwixt the blower and intake before you bolt down the blower.Again using the pattern in the manual, torque the blower down first to 15 lb-ft and then, on the second pass, to 22 lb-ft of torque. The 3×5 rotor combination found inside this 2.9-liter blower is said to improve airflow, and, thus, performance under the curve.Oh yeah! The jackshaft cover is carbon fiber and embossed with the Whipple logo. It not only keeps you from touching the spinning shaft, but it looks great. With it bolted down, Harvey makes all the wiring and vacuum hose connections, including relocating the EVAP solenoid on a nicely engineered bracket.Continuing on with the hardware, Harvey mounted the optional SPAL 11-inch fans on the ample Whipple heat exchanger. The combination of large radiator, big reservoir, and matching pump are said to circulate 1.3 gallons of coolant and really reduce blower-discharge temps.After removing indicated fasteners from the bumper and the two bumper support bars, Harvey maneuvers the heat exchanger into place. There is plenty of room in front of the S550 radiator for this setup, and with the Lethal grille delete in place it will receive plenty of airflow.We were a bit late on this step, but the Whipple kit includes shorter heater tubes designed to work with the hose modifications we covered earlier. These tubes are a direct replacement for the stock tubes, which you can see are much taller.With things progressing nicely, Harvey uses a larger wrench to release the spring-loaded tensioner and install the new, longer six-rib belt, following the diagram in the instruction manual. With the belt on, he then maximized the belt tension with by setting the lone adjustable idler pulley and bolting it into place.Harvey then went about making the rest of the hose and wiring connections. The Whipple kit does offer an OE-level of fit and finish. Most of its replacement hoses and wiring extenders feature factory-style connectors for an easy, plug-and-play install.The intercooler reservoir is mounted down low using factory fasteners and the intercooler pump is clamped right to it so pump starvation shouldn’t be an issue. It’s the little touches like this that we really appreciated about this kit.With the intercooler reservoir mounted, Harvey turned his attention to the air box. He assembled the box with the rubber seal, large mass air sensor housing, and the filler neck for the intercooler reservoir. As you can see here, he already swapped the slot-style mass air electronics into the Whipple housing. With the box assembled, you will want to install the air filter before maneuvering it into place, as the air filter is a tight fit with the inner fender.You can opt to run either the stock 80mm round throttle body or one of Whipple’s 132mm elliptical units, which we affectionately dubbed the “roval.†Knowing that positive-displacement blowers detest inlet restrictions, Lethal opted to run the larger Whipple unit. This means swapping over the stepper motor that Harvey is transplanting here.The 132mm Crusher throttle body bolts right onto the front inlet of the 2.9-liter supercharger. If you do opt to run the stock throttle body, the kit designed for that unit comes with an adapter plate for the blower inlet. Just don’t expect to make the same kind of power as you would with the Crusher.With the throttle body and air box in place, Harvey installed the carbon fiber inlet elbow with the supplied silicone couplers. Be sure not to over-tighten the clamps, as you might crack the elbow. It’s clear that this setup offers a low-restriction air path.In order to power the intercooler pump and heat exchanger fans, it is necessary to tap into the factory electrical system at the underhood fuse box. This is easily achieved with the supplied harness, which has all the necessary connectors and relays.Harvey routed the harness from the fuse box down along the radiator core support and plugged the connectors into the fans and intercooler pump.Before you even think about starting the car, be sure to add the proper amount of the supplied lubricant to the gear case at the rear of the blower. The blowers are shipped dry, so if you run them without oil in the blower transmission, it will cause damage.The kit looks like a OEM supercharger application. Only the stunning paint match to wrap lets you know that this Coyote is something special.Almost any modification on a modern Mustang requires a PCM calibration, and that’s especially true of a major modification like the a supercharger upgrade. Whipple offers its own calibration for the TriCor PCM in the latest Mustang. It dials in the fuel, spark, knock detection, torque management, transmission control and electronic throttle control. The latter is particularly important when you chose the 132mm Crusher throttle body.While the Whipple kit comes with a set of larger fuel injectors to provide the necessary fuel for the supercharger’s added airflow, Lethal opted to install one of JMS Chip & Performance’s new plug-and-play FuelMax pump voltage boosters on the car to allow for greater performance in the future. This unit not only provides a steady flow of voltage to the pump, but it offers a user-adjustable increase, up to 85 percent, in fuel flow. We’ll give more detail on this unit’s installation soon.With the new supercharger pushing 11 psi and the Whipple-supplied calibration in the TriCor PCM, the Lethal GT put down 700.51 horsepower and 521.85 lb-ft of torque.This a look at the blower versus Lethal’s first round of NA bolt-ons. However, we last left off with the 434.56 horsepower and 403.85 lb-ft of torque with the addition of the American Racing Headers exhaust. As such, the blower added stout peak-to-peak gains of 265.89 horsepower and 118 lb-ft of torque.When we can, we like to look at a sampling of the data to illustrate those under-the-curve gains. Matching up our previous baseline with the ARH system, you can see the Whipple supercharger brings stout gains in the midrange, and pulls really hard at the top of the tach.
2 thoughts on “Tech: 2015 Mustang Whipple Install”