When it comes to maximizing performance on a Honda K-Series engine, exhaust flow is a key factor in extracting every bit of power. One of the most effective upgrades for the EP3 Civic Type R, DC5 Integra Type R, and K-swapped cars is a 70mm exhaust system. But what makes 70mm the optimal choice, and what performance benefits can you expect? Let’s break it down.

Why Choose a 70mm Exhaust System?

The factory exhaust on many Honda K-Series cars is restrictive, often around 60mm in diameter. While this is adequate for a stock setup, it can limit performance when additional modifications such as intake, headers, and tuning are introduced. A 70mm exhaust system provides:

• Increased Exhaust Flow – Reducing back pressure allows the engine to expel gases more efficiently, improving power output.

• Enhanced Mid-to-Top End Power – Ideal for high-revving VTEC engines where power is made in the upper RPM range.

• Deeper, More Aggressive Exhaust Tone – A larger exhaust diameter produces a more refined, race-inspired sound without excessive drone.

• Optimized for NA and Forced Induction Builds – Whether naturally aspirated or boosted, a 70mm exhaust supports higher horsepower goals.

Performance Gains You Can Expect

The horsepower and torque improvements from a 70mm exhaust depend on supporting modifications. However, typical gains include:

• 5-10 horsepower on a bolt-on K20A/K20A2 with an upgraded intake and headers.

• 10-15 horsepower with a fully optimized bolt-on setup and ECU tuning.

• Even greater gains on high-compression or forced induction setups, as the increased flow capacity prevents restriction.

Best Applications for a 70mm Exhaust

A 70mm exhaust system is perfect for:

• Honda EP3 Civic Type R (K20A2) – Allows the high-revving K20A2 engine to breathe more efficiently, especially with supporting mods.

• Honda DC5 Integra Type R (K20A) – Enhances the already potent K20A engine, improving top-end power and throttle response.

• K-Swapped Honda Chassis (EK, EG, DC2, etc.) – A crucial upgrade for K-swap projects where maximizing performance is the goal.

Top Exhaust Brands to Consider

For those looking to invest in a high-quality 70mm exhaust system, here are some top options:

• Toda Racing – Renowned for high-performance, track-proven exhausts with precision engineering.

• Spoon N1 – A great option for those wanting a race-inspired system with a unique tone.

• Mugen – Offers high-quality craftsmanship and optimal performance for K-Series engines.

• Skunk2 MegaPower R – A budget-friendly option that still delivers impressive gains.

Final Thoughts

If you're serious about extracting maximum performance from your EP3, DC5, or K-swapped Honda, upgrading to a 70mm exhaust system is a must. The improved flow, increased horsepower, and aggressive tone make it a worthwhile investment for any Honda enthusiast.

Looking for the best 70mm exhaust options? Check out our selection at Type Two Online and take your VTEC-powered build to the next level!