AEM 21-778C Cold Air Intake System (Non-CARB Compliant)

✔ Vehicle Fitment

• 2018 Hyundai Elantra – L4 2.0L

• 2019 Hyundai Elantra – L4 2.0L
  
  Make sure you’ve got the 2.0L engine, since AEM lists this part for that fitment only

The AEM 21-778C Performance Cold Air Intake System produces horsepower and torque gains by replacing your vehicle’s restrictive factory air filter and air intake housing. This air intake system was designed, tuned and dyno-tested to fit specific Mitsubishi Lancer models.

Why This Intake Is Worth It

Here’s the deal: Hyundai gives you a “reliable everyday engine” but with an intake path that seems designed for whispering rather than roaring. With the AEM 21-869C you get:

• Improved airflow: Low-restriction aluminum tubing helps your engine inhale more freely. aemintakes.com

• Sharper throttle response: Less intake restriction means your foot gets rewarded sooner.

• Better engine sound: You’ll actually hear the 2.0L breathing instead of it acting like it’s underwater.

• Dryflow filter: A washable, reusable oil-free filter means less mess and better long-term reliability.

• Gunmetal grey finish: The aluminum intake tube is powder coated for durability and looks.

Estimated gains on this model: +8.15 hp @ 5805 rpm according to AEM.

Air enters the system through an oversized AEM Dry flow synthetic washable air filter for outstanding air flow, filtration and performance. The air filter is relocated to be in driver-side wheel well which is designed to reduce intake air temperature and increase horsepower.

Key Features

• Mandrel-bent aluminum intake tube (gunmetal grey)

• AEM Dryflow synthetic, oil-free filter rated up to ~100,000 miles before cleaning depending on conditions.

• Heat shield to reduce intake temperature from engine bay heat.

• Designed to retain factory sensors, breather tubes and mounting points for direct fit.

• Note: Not legal for sale or use in California on pollution-controlled vehicles.

The lower air intake tube is a free-flowing, mandrel-bent aluminum tube with a durable gunmetal gray powder coat finish. The upper air intake tube is a roto-molded, aerodynamically engineered, HDPE tube that insulates the cooler intake air from heat as it passes through the engine bay and into the engine’s throttle body.

Performance Expectations

On your Elantra 2.0L, you can expect:

• Quicker throttle tip-in and better responsiveness

• Improved mid-range acceleration feel

• A more engaging engine sound when you push it

• Slight horsepower gains (~8 hp as claimed) though real world results vary

• Better airflow foundation for future mods if you go that route

This air intake system was developed to accommodate the Lancer’s factory emissions control devices including the mass airflow sensor and PCV hose. The tapered cylinder shaped AEM Dry flow air filter is made from an oil-free, synthetic filter media that can be used for up to 100,000 miles before cleaning is needed (depending on driving conditions).

Daily-Driver Friendly

Yes — good news: you don’t have to compromise functionality for fun.

• Works with the factory ECU, no immediately required tune.

• Dry filter means easier maintenance (no oiling required).

• Keeps daily drivability intact while adding a layer of performance.

• Just make sure to check local laws because it’s not CARB-legal in California.

The air intake system is backed by AEM’s Lifetime Limited Warranty.

Installation Overview

Expect about 45–75 minutes with basic hand tools:

1. Remove the factory airbox, filter, and intake ducting.

2. Install AEM’s heat shield and intake tube per instructions.

3. Mount the Dryflow filter in the new assembly.

4. Reconnect sensors, clamps, check for clearance and secure everything.

5. Start engine, listen for induction tone, check for check-engine light.

No cutting, no complex modifications — but some elbow grease and patience will save you headaches.

Some AEM air intakes are not legal for sale or use in California and other states adopting California emission standards, while others are 50 state legal. View the 21-778C vehicle applications to determine the legal status for each vehicle.