There is no question that the DOHC 5.0L Coyote engine has taken Mustang performance to new levels, and the spotlight, but if you have a Three-Valve 4.6L, there are still a lot of performance options available to increase the fun factor. Ported heads, larger camshafts, and boost can all take you to the next level—but even with an intake manifold as efficient as the stock one, performance can be limited.
Since it's introduction in the Mustang in the '05 model year, the Three-Valve 4.6L has had an amazing amount of support from the aftermarket. During its infancy, new parts seemingly hit the market every day. Among the slew of appearance upgrades and basic bolt-on performance parts, some hardcore go-fast goodies were designed and manufactured for those looking to go quicker and faster than most Mustang owners.
C&L Performance, Ford Racing Performance Parts, and JPC Racing each released an aftermarket intake manifold for Three-Valve Mustang engine. The designs are different, but the goal is the same—more power. The intakes are now within $200 of each other, but how do they perform? This month we are going to test each one on a naturally aspirated Three-Valve so you can see the results. Next month we will bring you the same test on a supercharged Three-Valve so you can see how horsepower is affected with boost.
The Subject— Blow-By Racing's '05 Mustang GT
For our Three-Valve intake test, we headed to Blow-By Racing in Boca Raton, Florida. One of the company's shop cars is an '05 GT with ported heads and aggressive camshafts, which makes it a perfect candidate for our test. Consistency for the test was extremely important, so each test was performed with air temperatures in the shop between 80 and 83 degrees, 195-degree water temperature, and a consistent 30 degrees of ignition timing, which seemed to be the sweet spot for each manifold. The testing was done on a Dynojet 224 chassis dyno.
All vitals, including timing, water temp, and cam timing were monitored using the SCT Live Link data logging software. All of the horsepower numbers are shown using the SAE correction factor, and the multiplier was the same 0.98 for each run. We used a Ford Racing Performance Parts throttle body (PN M-9926-3V) and a JLT Performance cold-air intake (PN CAI3-FMG05) as a constant for all testing.
With the stock intake manifold, our test subject laid down 367 rwhp and 307 lb-ft of torque. All of our intakes will be compared to these numbers.