BMW M135i Vs Subaru WRX STI 320R: Track Test Verdict

Compact performance cars have evolved into track-capable machines, and few matchups highlight this better than the BMW M135i and Subaru WRX STI 320R. Both deliver 316 horsepower from turbocharged engines, promising intense competition on circuits like Blyton Park. This analysis breaks down their engineering, on-track prowess, and everyday appeal to determine which excels.

Powertrain Breakdown: Matching Outputs, Different Characters

The BMW M135i features a 3.0-liter straight-six turbocharged engine, renowned for its smoothness and broad powerband. It produces 316 horsepower and 450 Nm of torque, available from just 1,250 RPM, enabling explosive low-end acceleration. Power routes through a six-speed manual standard or optional eight-speed automatic, prioritizing rear-wheel drive for dynamic handling.

In contrast, the Subaru WRX STI 320R uses a 2.5-liter turbocharged flat-four, also yielding 316 horsepower but with peak torque arriving later around 3,000 RPM. Its symmetrical all-wheel-drive system and six-speed manual transmission emphasize rally heritage, distributing power for superior traction in varied conditions.

These specs show parity on paper, but real-world delivery sets them apart.

On-Track Performance: Lap Times and Dynamics at Blyton Park

During the Auto Express track test, the BMW M135i clocked a 1:14.05 lap, edging out the Subaru’s 1:16.00 by nearly two seconds. The BMW’s early torque surge propelled it through corners with minimal gear shifts, hitting nearly 100 mph in sections while maintaining composure.

The Subaru demanded more driver input; its higher torque onset required revving to unlock peak performance. Despite AWD grip, it exhibited more weight transfer, tire squeal, and oversteer corrections in high-speed esses. Steering felt lighter with less feedback, though it carried speed well in mid-corner phases.

• BMW Strengths: Instant throttle response, rapid revving to 7,000 RPM, precise shifts from the DCT option.
• Subaru Strengths: Tenacious AWD traction, raw engine character, stability under hard braking.
• Common Challenges: Both struggled with trail braking and exit traction, but BMW felt more planted.

Video analysis confirms the BMW’s superior lap pace stems from its balanced chassis and power delivery.

Handling and Chassis Tuning: Precision vs Rally Grit

BMW’s rear-drive layout shines in direction changes, offering sharp turn-in and neutral balance. Run-flat tires and stiff suspension provide high-speed stability, though some note understeer under aggressive provocation. The M135i’s silky engine note enhances the premium feel.

Subaru’s setup, with its lowered stance and WRX STI tuning, prioritizes foul-weather prowess. AWD mitigates slip on uneven surfaces, but added weight (despite being marginally lighter) induces body roll and nose-heaviness in tight corners. It’s rewarding for skilled drivers who exploit its adjustability.

Forum enthusiasts debate this: BMW owners praise refinement, while STI fans value the ‘raw’ engagement.

Braking and Tires: Stopping Power Under Pressure

Both cars feature performance brakes, but track sessions reveal nuances. BMW’s system allows confident trail braking into apexes, aided by RWD ABS tuning. Subaru’s AWD setup provides shorter initial bite but demands modulation to avoid lockup.

Tire compounds are sticky summer rubber on both, with BMW exhibiting less wear and more progressive grip loss. Subaru’s wider contact patch aids straight-line braking but highlights chassis limitations in transitions.

Pricing and Value: Premium German vs Japanese Workhorse

Launched around 2012-2013, the BMW M135i started at £30,555 (three-door manual), positioning it as a premium hot hatch. The Subaru WRX STI 320R, at £34,594, carried a slight premium for AWD and rarity.

Today, used examples reflect this: M135i models hold value for their engines, while STIs appeal to rally enthusiasts. Running costs favor Subaru’s simpler maintenance, though BMW offers superior interiors.

Everyday Usability: Beyond the Track

Daily driving favors the BMW’s compliant ride, quick DCT shifts in traffic, and upscale cabin. Fuel economy hovers around 25-30 mpg combined, with effortless overtaking.

Subaru excels in wet roads, with AWD confidence, but firmer suspension transmits more road noise. Its functional interior prioritizes durability over luxury.

Long-Term Ownership Insights

BMW M135i owners report reliable N55 engines with proper cooling, though DCT maintenance is key. Subarus demand vigilant turbo and AWD care, but deliver rally durability. Resale remains strong for both due to enthusiast demand.

Which One Wins?

The BMW M135i claims victory on pure track metrics, blending speed, poise, and accessibility. Subaru WRX STI 320R fights valiantly with grip and character, ideal for rally-style adventures. Choose based on priorities: refinement or ruggedness.

Frequently Asked Questions (FAQs)

Which car is faster on track?

BMW M135i lapped Blyton Park in 1:14.05 vs Subaru’s 1:16.00.

Is the BMW manual or automatic better?

DCT option shifts faster for track use; manual suits purists.

Does AWD make Subaru better in rain?

Yes, superior traction in wet conditions.

What are common mods for these cars?

Both benefit from exhausts, tunes, and suspension upgrades.

Are they still worth buying used?

Absolutely, for performance per dollar.