Wes Duenkel
June 1, 2018
Photos By: Erik Radzins

Ford’s third-generation 5.0L Coyote V8 engine powering the latest 2018 Mustang GT is a high-tech wonder. Besides sporting direct fuel injection, the Gen-3 Coyote features a significant compression ratio bump to 12:1 (up from the previous 11:1). The result is a historic 460 horsepower and 420 lb-ft of torque from the five-liter mill.

Despite their relatively high compression ratios, 2011-2017 Coyotes withstood surprising amounts of boost. But would the current Mustang’s direct fuel injection and even higher compression ratio prove too hostile for supercharging?

We got the skinny from ProCharger’s Erik Radzins. “The Mustang is able to blend between port and direct injection, creating the virtual ‘best of both worlds’ scenario. Thankfully we have some amazing partners in the industry of tuning these new ECUs. So about as fast as we have a system onto the car for R&D testing and assessment, we have the support of the tuning companies to crack deep into the engines ECU for the control functions we need. Not only for overall power numbers, but for smooth driving habits, and our focus on clean, [California] E.O. friendly performance. We are making a HUGE push in getting the vast majority of our supercharger systems 50 state legal, and these 2018’s will be no different.”

ProCharger’s offerings for 2018 Mustang GTs fall into two basic categories: “H.O.” and “STG2.” The H.O. Supercharger system utilizes the Mustang’s existing six-rib accessory belt system to spin a P-1SC-1 or P-1X blower, and either a 630 square-inch or 1103 square-inch intercooler. The H.O. kits are set up for 6.5 PSI of boost.

STG2 supercharger systems upgrade to a dedicated 8-rib belt system, and include a fuel pump booster and the larger 1103 square-inch intercooler. STG2 kits include pulleys that net 8.5 PSI of boost. As usual, ProCharger offers “tuner” versions of each system that leave the PCM programming and final boost level up to the installer.

The system can be installed over a weekend in a garage with common hand tools. ProCharger’s self-contained oiling systems mean there’s no oil lines to run, and the included fuel pump booster and tune eliminates the need to swap fuel injectors.

In the “bang per wrench” category, the results are staggering: with a modest 7.6 PSI measured boost, the STG2 system netted 676 horsepower and 512 lb-ft of torque at the rear wheels on ProCharger’s Mustang chassis dynamometer. That’s 276 horsepower and 155 lb-ft more than stock!

With customers already launching ProCharger STG2-equipped 2018 GTs into the 9s at the dragstrip, we wanted in on the action. Is it really that easy to add 69% more horsepower to a new Mustang? The folks at ProCharger agreed to walk us through a STG2 ProCharger system installation on a fresh 2018 model.

1. Here are the major under-hood parts of the ProCharger STG2 supercharger system for 2018 Mustang GTs: P-1X blower, air-to-air intercooler, pulley system, and all necessary tubing. (Not pictured are the tuning device and fuel pump booster.)

2. ProCharger’s Phillip VanBuskirk shows off the differences between the STG2’s 1,103 square-inch intercooler (left) and the H.O. kit’s 630 square-inch unit.

3. We began the installation process by removing the strut tower brace, engine cover, and cold air intake system.

4. Next, we removed the front fascia to gain access to the front of the car. This makes installing the STG2 kit’s large by huge intercooler possible, as well as some of the other components.

5. Because we’ll be installing a different coolant expansion tank and thermostat housing, we drained a couple gallons of coolant from the system and set it aside.

6. The ProCharger head unit bracket interferes with the stock thermostat housing, so we installed the supplied ProCharger thermostat housing to allow the necessary clearance.

7. Next, we swapped out the stock radiator brackets for the supplied pieces.

8. Then, we transferred the mass air flow (MAF) sensor from the stock air intake tube to the Procharger intercooler tank.

9. Next, we slipped the ProCharger intercooler into place behind the front bumper.

10. It’s hard to miss the ProCharger STG2 intercooler on this Mustang.

11. The ProCharger STG2 supercharger system drives the blower via a dedicated 8-rib belt that piggybacks on the stock crankshaft pulley.

12. We installed the supplied supercharger idler pulley atop the OEM unit.

13. Next, we installed the necessary hardware and standoffs to mount the ProCharger head unit bracketry.

14. Then, we carefully installed the P-1X head unit and bracket on the front of the engine.

15. With the bracket’s fasteners tightened to spec, we installed the supplied 8-rib belt.

16. Next, we preloaded the blower belt tensioner per the detailed instructions included with the ProCharger kit.

17. Then we connected the tubing and filter for the supplied ProFlow surge valve.

18. The ProCharger kit includes a filter and tubing the draws cold air from behind the front fascia.

19. Next, we focused on the plumbing for the pressurized side of the system. We connected the throttle-body to the intercooler with the supplied tubing and silicone couplers.

20. ProCharger includes this trick fabricated coolant expansion tank the replaces the factory plastic piece.

21. To supply with the additional fuel needed to accompany the forced induction, ProCharger supplies a fuel pump booster that strategically increases the fuel pump output when needed.

22. We spliced the fuel pump booster into the fuel pump driver module’s wiring harness, and completed the remaining power and ground connections.

23. Back in the engine compartment, we installed the supplied pressure switch into the vacuum manifold and connected it to the fuel pump booster in the trunk with the supplied wiring harness.

24. Underhood work concluded by reinstalling the front fascia, engine cover, and strut tower brace.

25. Before firing the engine, we recalibrated the Mustang’s PCM with the supplied programmer.

26. After topping off the coolant system and checking all the connections, it was off to ProCharger’s in-house dynamometer for some power runs.

27. Does the 2018 Mustang GT’s direct-injected and 12:1 compression Coyote engine like boost? Yes! At a modest 8.5 PSI of maximum boost, the STG2 system netted 676 horsepower and 512 lb-ft of torque at the rear wheels That’s 276 horsepower and 155 lb-ft more than stock!