How Much Does It Cost to Reach 400 Hp on an Evo 9? Parts, Tuning, and Labor

Understanding the Evo 9’s Potential and the 400 hp Target

The Mitsubishi Lancer Evolution IX is widely regarded as one of the most capable turbocharged all-wheel-drive platforms ever produced. Powered by the legendary 4G63T engine, the Evo 9 benefits from MIVEC variable valve timing, a stronger block than earlier iterations, and a factory turbocharger that responds well to modest upgrades. Reaching 400 horsepower—whether measured at the crank or the wheels—is a popular milestone that offers a dramatic increase in acceleration and top-end pull without pushing the engine beyond its reliable limits.

Achieving this figure requires a coordinated set of modifications. The 4G63 engine is notoriously robust, but fuel delivery, airflow, and thermal management must all be addressed to keep the motor happy at this power level. This article provides a comprehensive cost breakdown covering every essential part, the labor involved, and the tuning required to hit 400 hp on an Evo 9. Prices reflect current market averages from reputable suppliers and tuning shops as of 2025.

Key Components for Reaching 400 hp

Every 400 hp build starts with several core upgrades. The factory turbo, injectors, and intercooler will not support this output reliably. Below we examine each major component, its function, and what you can expect to spend.

Turbocharger Upgrade

The stock TD05HR-16G6 turbo on the Evo 9 is capable of roughly 300–330 whp on pump gas. To reach 400 hp you need a larger compressor wheel and turbine housing. Popular choices include the MHI 20G, the FP Green, the Garrett GT3076R, or precision-journal bearing turbos. A direct bolt-on replacement such as the MAPerformance Stage 3 or ETS Extreme kit ranges from $1,400 to $2,800. For a top-tier ball-bearing unit with a billet wheel, expect to pay up to $3,500.

Fuel System Upgrades

Higher airflow requires proportionally more fuel. The factory 560 cc/min injectors will max out around 350 whp. For 400 hp you need 1000 cc/min or larger injectors. Walbro 255 lph or 450 lph in-tank fuel pumps are standard. A complete fuel system upgrade—injectors, pump, and a fuel pressure regulator—costs between $600 and $1,400. If you switch to a return-style fuel system for easier tuning, add another $300–$600.

ECU Tuning

Proper calibration is the linchpin of any reliable build. The Evo 9 ECU can be reflashed using OpenECU or EcuFlash with a Tactrix cable, or you can run a standalone like the Haltech Elite 2500 or the ECUmaster Black. Professional tuning labor runs $400 to $1,200 depending on the complexity and whether you use a remote tuner or a local dyno facility. A reflash with a wideband O2 sensor kit typically costs less than a full standalone installation and tune.

Exhaust System Enhancements

A restrictive exhaust strangles a 400 hp build. A 3-inch turbo-back exhaust with a high-flow catalytic converter (or test pipe) and a compatible downpipe is mandatory. Quality systems from HKS, Injen, or Tomei range from $700 to $1,500. If you already have a cat-back, adding a 3-inch downpipe and race cat costs about $400–$800.

Intercooler Upgrades

Intake air temperatures rise quickly at higher boost levels. A larger front-mount intercooler reduces charge temps by 30–50 degrees. Reputable FMIC kits from ETS, PRL, or Spearco run between $900 and $1,600. A cheaper bar-and-plate unit may work but often requires trimming of the crash beam. Do not skip this upgrade—knock prevention depends on cool intake air.

Intake and Exhaust Manifolds

While not always essential for 400 hp, a ported or aftermarket intake manifold (like the JMFabrications or Magnus V2) can improve top-end power by 15–25 hp. Costs range from $500 to $1,200. An upgraded turbo exhaust manifold, preferably tubular stainless steel, reduces spool time and adds torque; prices fall between $600 and $1,200. These two parts together push you closer to the target but can be deferred if you are on a strict budget.

Cams and Valve Train

The stock MIVEC cams are good to roughly 450 hp, but for maximum response at 400 hp, replacing the cam gears with adjustable units and upgrading to Kelford 272° or GSC S2 cams is common. A cam kit with springs and retainers costs $900–$1,600. Installation labor adds another $500–$900 because the timing cover and belt must be removed.

Supporting Modifications for Reliability

Reaching 400 hp is one thing; keeping the engine alive is another. The following items are strongly recommended to prevent premature wear and catastrophic failure.

Clutch and Flywheel

Factory clutches slip around 350–380 whp. A twin-plate clutch like the ACT Twin Disc or South Bend Stage 3 holds well and provides a reasonable pedal feel. Budget $900–$1,500 for a clutch kit. A lightweight flywheel reduces rotational inertia and costs $300–$500. Labor for clutch replacement is typically $600–$1,000 due to the all-wheel-drive drivetrain.

Cooling System

At 400 hp sustained under hard driving, coolant temperatures can climb. A Koyo or Mishimoto aluminum radiator ($400–$600) and a Setrab oil cooler ($300–$600) help maintain safe temps. Upgraded silicone hoses ($150–$300) prevent burst lines under high boost.

Head Studs and Head Gasket

The 4G63 is prone to lifting the cylinder head at higher cylinder pressures. ARP head studs ($150–$200) and a Cometic multi-layer steel head gasket ($150–$250) are cheap insurance. Install labor for head studs alone is about $300–$500 if done during a timing belt service.

Differential and Transfer Case

The Evo 9 stock viscous coupling and rear limited-slip differential can handle 400 hp for street driving, but aggressive launches may cause wear. A clutch-type rear LSD upgrade ($800–$1,500) is recommended for track use. Budget $1,200–$2,000 for a full rebuild with upgraded plates if your car has high mileage.

Tuning Options and Costs

Tuning is not simply paying a shop to push a button. The ECU must be calibrated for the specific fuel (pump gas, E85, or race fuel), boost level, and all the new components. Below are the three most common paths:

Reflash via EcuFlash – Uses a Tactrix 2.0 cable ($180) and free software. You pay a tuner for an e-tune ($300–$600) and load the ROM yourself. Requires a laptop and some technical comfort.
Dyno Tune – Local shop installs parts and tunes on a dyno. Rates are $100–$200 per hour; a full tune takes 3–5 hours. Total $500–$1,200.
Standalone ECU – Haltech, Link, or AEM Infinity. Cost of ECU ($1,500–$2,500) plus wiring and tune ($1,000–$2,000). This path adds total $2,500–$4,500 but gives unlimited control for future upgrades.

If your goal is exactly 400 hp on pump gas, a reflash tune with a quality dyno session is the most cost-effective route.

Labor Costs: Installation and Fabrication

Labor rates vary widely by region. Independent performance shops charge $100–$150 per hour; dealerships or high-end tuners may charge $150–$250 per hour. Installing the bolt-on parts (turbo, injectors, FMIC, exhaust, intake, and wiring wideband) typically takes 15–25 hours. At $125/hour average, that is $1,875–$3,125. If you do the work yourself, you save this entire amount, but you need tools, a lift or safe jack stands, and mechanical experience.

Additional labor items that often arise:

Custom piping for a rotated turbo setup: +$500–$1,000
Boost controller installation and wiring: +$200–$400
E85 sensor installation: +$300–$600
Fuel pump rewire kit: +$150–$300

Total Estimated Cost Breakdown

Combining all essential parts, tuning, and labor, here is a realistic range for a 400 hp Evo 9 build. These numbers assume you purchase new aftermarket parts and pay a shop for installation and tuning.

Component	Low Estimate	High Estimate
Turbocharger upgrade	$1,400	$3,500
Fuel system (injectors, pump, regulator)	$600	$2,000
ECU tuning	$400	$1,200
Exhaust system (turbo-back)	$700	$1,500
Intercooler kit	$900	$1,600
Intake and turbo manifold (optional)	$1,100	$2,400
Clutch and flywheel	$1,200	$2,000
Reliability items (head studs, cooling, etc.)	$1,200	$2,500
Labor (parts install + tune)	$1,800	$4,000
Total	$9,300	$20,700

Note that a bare-bones build using a bolt-on turbo, used parts, and self-installation can be done for roughly $4,500–$6,000, but reliability and power consistency suffer. Most owners who want a streetable, reliable 400 hp spend between $10,000 and $14,000.

Real-World Build Examples

Budget Street Build (~$7,000)

Used MHI 20G turbo ($900)
Walbro 450 pump and 1000 cc injectors ($500)
ETS 3.5" FMIC kit ($950)
Used 3" exhaust ($500)
EcuFlash reflash tune by a remote tuner ($450)
Labor (friend mechanic, lift access) ($500)
Total: ~$3,800 in parts, $500 labor, $450 tune

Premium Track Build (~$18,000)

Garrett GTX3076R Gen II ($2,600)
Full return-style fuel system, E85 conversion ($1,500)
Haltech Elite 2500 with plug-in harness ($2,200)
Titanium exhaust ($2,000)
ETS Race FMIC ($1,600)
GSC S2 cams with springs ($1,600)
ACT Twin Disc clutch ($1,500)
Head studs, MLS gasket, oil cooler, radiator, water injection ($3,000)
Professional dyno tune and fabrication labor ($2,000)

Both builds hit 400 whp on pump gas. The budget car runs 23 psi on a medium-sized turbo and may show higher intake temps; the premium car runs 25 psi with much cooler charge temps and holds that power lap after lap.

Reliability and Maintenance Considerations

Once you cross 400 hp, the weak points become the drivetrain and the cooling system. Regular oil changes with a 5W-40 full synthetic are mandatory. The factory 4G63 bottom end can handle 400 whp for many street miles if tuned conservatively, but aggressive timing or sustained high boost on pump gas will cause knock and eventually ring land failure.

Consider the following maintenance steps:

Upgrade the oil pickup tube to a “trap door” style to prevent starvation under hard cornering ($200–$400).
Install a boost gauge, wideband O2 sensor, and oil pressure gauge to monitor conditions.
Replace the timing belt and water pump every 60,000 miles or at the time of the build if they are due.
Upgrade the transmission and transfer case breathers for track use.

External links for further reading:

Final Thoughts

Reaching 400 hp on an Evo 9 is an entirely realistic goal for a disciplined builder. The engine architecture supports it; the aftermarket is deep; and supporting tuners are experienced. Your total investment can range from a few thousand for a bare-bones build to over $20,000 for a turnkey, bulletproof setup. The key is to prioritize the turbo, fuel, and tune, then add supporting mods as your budget allows. With proper maintenance and a good tuner, a 400 hp Evo 9 offers a stunning blend of road car usability and track day performance that few other platforms can match.