Porsche 718 Cayman GT4 / Ford Mustang GT S550

The Porsche 718 Cayman GT4 makes 414 horsepower and costs $125,000. The Ford Mustang GT S550 makes 435 horsepower and costs $47,500—a $77,500 price gap (163% more expensive for the Porsche) despite the Mustang having 21hp more power. Across 60 shared tracks with 480 unique comparison scenarios, the GT4 wins by 3.88 seconds overall, and when you filter the comparison data on this page for matched modifications and matched tire treadwear, the GT4 wins 91.1% of battles with a 6.47-second average gap.

This is Porsche's mid-engine track weapon versus Ford's S550 Mustang GT (2015-2023). The GT4 weighs 3,247 lbs. The Mustang weighs 3,705 lbs—458 pounds heavier. The Mustang has 21hp more power (435hp vs 414hp), yet the GT4 wins 91.1% of matched battles. The question isn't which is faster—the GT4 dominates. The question is whether mid-engine perfection justifies paying $77,500 more when the Mustang has more power.

The Mid-Engine Advantage: Physics Over Power

The Mustang's Coyote 5.0L V8 makes 435hp at 6,500 rpm and 400 lb-ft at 4,250 rpm. Power-to-weight: 8.52 lbs/hp. The GT4's 4.0L flat-six makes 414hp at 7,600 rpm and 310 lb-ft at 5,000-6,800 rpm (database shows 429.79 lb-ft, likely with optional sport exhaust). Power-to-weight: 7.84 lbs/hp—an 8% advantage despite having 21hp less.

The GT4's mid-engine layout places the 414hp flat-six directly behind the driver, creating telepathic handling and instant rotation. The Mustang's front-engine layout with 53/47 weight distribution is nose-heavy—fast in straight lines but less agile through corners. The GT4 has less power (21hp deficit) but wins 91.1% of matched battles through chassis superiority alone.

What the Filtered Data Reveals

• Matched mod + matched tire (157 laps): GT4 wins 91.1%, Mustang wins 8.9%, 6.47s gap. When both run equal preparation and tires, the Porsche's mid-engine advantage overwhelms the Mustang's 21hp power edge. The Mustang wins fewer than 1 in 10 battles—proof that power alone doesn't win races.
• Matched mod, mismatched tire (232 laps): GT4 wins 81.5% with 5.04s gap. The tire mismatch scenarios often show the GT4 on street tires versus Mustang on R-compounds, yet the Porsche still wins more than 8 out of 10 battles.
• Light GT4 vs race Mustang, TW200/40 (46 laps): GT4 wins 65.2% with 5.99s gap. When the Mustang runs race-level modifications with R-compounds (likely supercharged at 650-700hp) against a lightly-modified GT4 on street tires, the Porsche STILL wins nearly two-thirds of battles. This is remarkable—a modified 700hp Mustang on slicks loses to a bolt-on 450hp GT4 on street tires.

The $77,500 Price Gap: What Are You Buying?

Mustang GT S550: $47,500 buys the Coyote 5.0L's 435hp, independent rear suspension (2018+), and strong aftermarket. The Coyote's modification ceiling is high: supercharger ($7,000-9,000) + supporting mods ($3,000) = 650-700hp. The comparison data shows that even at 700hp, the Mustang still loses 65% of battles to a lightly-modified GT4—proof that power can't compensate for mid-engine physics.

718 GT4: $125,000 buys mid-engine perfection, 414hp, GT3-derived suspension, and a chassis that wins 91.1% of matched battles despite having 21hp less power. The flat-six's modification ceiling reaches 450hp with exhaust ($4,000) + tune ($2,000). The GT4 doesn't need forced induction to dominate—the chassis advantage is that significant.

That $77,500 premium buys a car that wins more than 9 out of 10 matched battles and appreciates 5-8% annually as a modern Porsche GT4. Over five years, the GT4's value climbs from $125,000 to $150,000-185,000 (20-48% appreciation) while the Mustang drops from $47,500 to $42,000-45,000 (6-12% depreciation).

The Verdict

Choose the Ford Mustang GT S550 if you want American V8 performance at $47,500, accept losing 91.1% of matched battles, and value having 21hp more power on paper. The Mustang is the choice for buyers who want the best performance-per-dollar and don't mind losing nearly every battle to mid-engine cars.

Choose the Porsche 718 Cayman GT4 if you have $125,000 to spend and want the car that wins 91.1% of matched battles despite having 21hp less power. You're paying $77,500 more (163% premium) for mid-engine physics that can't be replicated through power alone. The GT4 is the choice for drivers who understand that lap times come from chassis, not horsepower.

LapMeta's 3.88-second overall gap and 6.47-second matched-condition gap show the GT4's superiority is overwhelming. The Mustang's 21hp power advantage and 435hp Coyote V8 can't overcome the GT4's 458-pound weight savings and mid-engine physics. For the driver who wants the best American V8 under $50,000, the Mustang delivers. For the driver who wants to win 91% of battles, the GT4's $77,500 premium buys measurable, undeniable superiority.