Metal vs Plastic Intake Manifolds

If you’ve ever looked under the bonnet on a newer car and spotted a plastic intake manifold, you might’ve wondered, hang on, isn’t that supposed to be metal?

This question comes up all the time in workshops, car meets, and group chats. So let’s break it down in plain terms.

Why the Switch to Plastic?

Car manufacturers moved to plastic for a few reasons. It’s cheaper, lighter, and easier to shape into complex airflow designs. Plus, it doesn’t heat up as fast as metal, so technically, it can keep air temps a bit cooler.

For your everyday stock car? Plastic does the job.

But once you start chasing power, especially anything boosted or tuned hard, plastic starts to fall apart (literally). We’ve seen them crack, warp, and even explode under big boost.

What’s Actually Good About Plastic Manifolds?

To be fair, plastic manifolds have a few upsides:

- Lightweight, so less strain on the engine bay.

- Quieter (yep, metal can be a bit rattly).

- Slightly cooler intake air at low to moderate loads.

- Cheap to replace when they break — and they will.

But at the end of the day, they’re made for cost efficiency, not performance.

Why Performance Builds Go Metal

If you’re serious about power, we’re talking boost, high RPM, or track abuse, a billet aluminium manifold is your best option.

Here’s why metal wins:

- It won’t flex, crack or melt under pressure.

- You can run more boost without worrying.

- It looks clean and tough under the bonnet.

- It’s CNC-machined for exact airflow, giving you max performance.

Of course we’re biased, sure, but only because we see the difference daily. Plastic is fine for mums picking up groceries. For your performance build? Aluminium all the way.

So Which One Should You Choose?

If your car’s stock and you’re just cruising around town, plastic will do the trick.

But if you're pushing power, adding mods, or just want something that lasts the life of your engine (and then some), go billet. It's not just a better material,  it's peace of mind every time you plant your foot.

Time to Ditch the Plastic and Go Billet?

If you're chasing power, reliability, and a setup that looks just as serious as it performs, a billet intake manifold is a no-brainer. Plastic might be fine for stock, but once you're in boost territory, it's only a matter of time before it lets you down.

We build our manifolds in-house, from solid 6061 billet, designed to handle serious horsepower and keep up with whatever you throw at it, whether that's street pulls, track days, or full-send drag passes.

- No more cracking under pressure
- No more worrying about heat soak
- Just solid performance and peace of mind

Hit the link below and check out our full range. Stock moves fast, if you’ve been thinking about it, now’s the time.
👉 Shop Billet Intake Manifolds