How Much Horsepower Does an Intake Manifold Upgrade Add?

When it comes to chasing horsepower, most people look at the usual suspects, turbo upgrades, fuel injectors, and ECU tuning. But the intake manifold? It’s often overlooked. 

Your intake manifold plays a critical role in how your engine breathes. It distributes air evenly across each cylinder, and the better the airflow, the better your engine performs, especially under load. So how much horsepower can an upgraded intake manifold really add? Let’s break it down.

What’s the Point of an Intake Manifold Upgrade?

From the factory, most intake manifolds are made with efficiency and cost in mind, not performance. They’re often cast aluminium or plastic, restrictive in design, and aimed at mass-market reliability rather than high-RPM power, and dont look premium in the engine bay. When you upgrade to a performance billet intake manifold, you're removing airflow bottlenecks, reducing heat soak, and creating a platform that can handle far more aggressive builds.

How Much Horsepower Can You Expect?

The horsepower gains from an upgraded intake manifold vary depending on your setup. On naturally aspirated engines, you might see modest gains, between 5 to 15 horsepower, primarily from better airflow and throttle response. However, in forced induction builds (turbo or supercharged), the story changes dramatically.

With high-boost applications, where airflow volume and pressure are critical, a well-designed intake manifold can unlock 20, 40, or even 100+ horsepower, depending on how restricted the previous setup was. On a full-blown drag build, it’s not unheard of to see an intake manifold be the difference between 1,500 and 2,000+ wheel horsepower.

CPC Manufacturing: Built for the Big Power

At CPC, we’ve taken all the guesswork out of what makes a proper intake manifold. Our billet manifolds are engineered in-house using 6061 aluminium, machined to exacting tolerances, and designed with performance-first thinking from plenum volume to bellmouth taper.

Our RB26 and JZ manifolds have been tested on some of the fastest cars in the world, Croydon Racing’s “Zeus,” for example, which makes over 2,000 horsepower and runs in the sixes. The drag-specific RB26 manifold comes with a 125mm throttle body, dual fuel rails, and is designed to support 12 to 24 injectors, depending on your setup.

Real-World Numbers: What Our Manifolds Handle

• RB26 & 2JZ Billet Drag Manifold – Tested beyond 2,000+ WHP

• 1JZ/2JZ and RB Billet Carbon Series – Suited for 1,000–1,800 WHP depending on injector and throttle body setup

• Street/Track Manifolds – For builds in the 500–900 WHP range, offering improved throttle response and power across the band

Every manifold is modular, allowing for upgrades, and includes o-ring seals, stainless fasteners, dual or single fuel rail compatibility, and DBW or cable throttle support

Do You Need an Intake Manifold Upgrade?

If you're building for looks and don’t plan to push big boost, a stock manifold might get you by. But if you’re serious about power, reliability, and want a showpiece that backs up the numbers, a billet intake manifold is a no-brainer.

It’s not just about the peak horsepower, it’s about consistent power delivery, better throttle response, and having a system that grows with your build. You wouldn’t run a race on retreads, why choke a high-performance engine with a stock manifold

Final Thoughts

In short, yes, an intake manifold upgrade can absolutely increase horsepower. On the low end, you might see 5–15hp, but in boosted applications, especially with supporting mods, that number can jump significantly. The real benefit comes in how your engine performs overall: smoother power curves, more top-end pull, and a setup that won’t hold you back.

So if you're running an RB26, JZ, or any high-performance setup, don’t overlook the intake manifold. It’s more than just an accessory, it’s the foundation of how your engine breathes.

And if you're ready to level up, check out our full range of billet intake manifolds, built in-house at CPC and tested on the world’s fastest builds.