McLaren 675LT Power Guide: 5 Proven Upgrades That Increase Horsepower
One of the most renowned Longtail models ever produced is the McLaren 675LT, a lightweight, track focused supercar designed for lightning fast acceleration and precise handling. Despite McLaren's superb engineering, a lot of enthusiasts look into high-performance upgrades to get more horsepower. Fortunately, the 675LT reacts very well to some modifications and using premium McLaren 675LT parts allows for significant power increases without compromising dependability.
Five proven improvements based on airflow, turbo efficiency, fuel mapping and cooling performance that genuinely boost horsepower are broken down in this guide.
1. ECU Tuning (Stage 1 or Stage 2)
An ECU tune is widely considered the most effective power upgrade for the McLaren 675LT. The stock engine map at McLaren receives a safe and protective calibration which fulfills worldwide regulatory requirements and emission rules and maintains engine reliability throughout its operational period. A professional ECU tune safely unlocks this unused potential.
Why does it boost horsepower?
- maximises the pressure of the turbo boost
- increases the air-to-fuel ratio
- improves the timing of ignition
- improves the throttle response
The majority of 675LT owners report gains of 60–90 horsepower with a Stage 1 tune and more than 100 horsepower with a Stage 2 tune (when combined with downpipes). The car becomes more aggressive to drive because its mid-range torque output has increased and its acceleration speed has improved without affecting its handling performance.
Best for owners who want-
The system provides instant power boost together with better throttle response and faster engine reaction speed.
2. High-Flow Downpipes
Another essential power modification for the 675LT is upgraded downpipes. Restrictive catalytic converters made to adhere to emissions regulations are part of the factory downpipes. Sport or high-flow downpipes enable the turbos to spool more quickly by lowering exhaust backpressure.
Why it increases horsepower
- Faster turbo spool
- Reduced exhaust restriction
- Improved airflow efficiency
Depending on the brand and configuration, high-flow downpipes can add 40–70 horsepower when combined with ECU tuning. Additionally, they give the 675LT a sharper, motorsport inspired tone by deepening the exhaust note.
Ideal for owners who desire-
Significant horsepower increases when paired with tuning, more aggressive sound.
3. Performance Exhaust System
A lightweight performance exhaust not only improves sound but also increases power by enhancing exhaust flow. Titanium and Inconel systems are particularly popular for the 675LT due to their low weight and heat resistance.
Why it increases horsepower
- Reduces backpressure
- Improves turbo efficiency
- Reduces vehicle weight
Power gains typically range from 10–25 hp but the biggest benefit is the dramatic reduction in weight- often up to 35–40 lbs depending on the system. Every pound matters in a Longtail and shedding weight enhances acceleration and handling.
Best for owners who want-
A louder, hotter exhaust note and better turbo response without major engine mods.
4. Upgraded Intercoolers
The 675LT operates as a turbocharged vehicle which requires denser cooler air to generate maximum power output. The installation of advanced intercoolers results in enhanced charge-air cooling performance which becomes vital for both aggressive driving and track activities because heat accumulation becomes a major constraint.
Why it increases horsepower
- Reduces intake temperatures
- Improves engine efficiency
- Allows more consistent power output
Lower intake temperatures allow the engine to maintain higher levels of performance without pulling timing. Owners typically see 10–20 hp gains and more importantly, consistent performance during repeated pulls.
Best for owners who want:
Consistent performance in hot climates or during extended driving sessions.
5. High-Performance Air Filters or Intake System
Airflow is the foundation of horsepower,and even small improvements in how efficiently air reaches the turbos can translate into measurable power gains. Aftermarket filters and carbon-fibre intake systems increase the engine’s breathing capacity.
Why it increases horsepower
- More efficient airflow
- Reduced intake restriction
- Improved turbo response
Power gains range from 8–15 hp, and although modest compared to tuning or downpipes, they become much more impactful when stacked with other upgrades. Intake upgrades also add stunning engine-bay aesthetics, especially with carbon fibre components.
Best for owners who want-
Affordable, reliable horsepower gains and improved turbo efficiency.
How to Choose the Right Upgrades
Before modifying your 675LT, consider:
- Your driving style (track-focused, weekend cruising, or daily fun)
- Budget (tuning and downpipes give the biggest value-to-power ratio)
- Parts quality (always choose reputable brands)
- Professional installation (McLaren engines require expert handling)
- Long-term reliability (proper tuning ensures safe performance gains)
The best approach is a balanced upgrade path- start with tuning, add downpipes, improve airflow and then move toward exhaust and cooling upgrades. Each upgrade enhances the next, creating a powerful and reliable system.
Conclusion
The McLaren 675LT already presents an exceptional driving experience but performance enhancements will make it an even more exciting vehicle. The combination of ECU tuning with downpipe upgrades and performance exhaust system and improved intercoolers and airflow systems produces actual horsepower increases which create an enhanced driving experience. Exotic Auto parts enable enthusiasts to obtain reliable components which include high-performance McLaren upgrades.