Upgrading to a full ETS (Extreme Turbo Systems) intercooler system on your Mitsubishi Eclipse GST is one of the most effective modifications for reducing intake air temperatures and supporting higher horsepower levels. Whether you are chasing a daily driver with extra punch or building a track-focused 4G63-powered machine, understanding the complete cost picture is essential. This expanded guide breaks down every component, labor consideration, and hidden expense you can expect when fitting a full ETS intercooler setup.

What Is an ETS Intercooler System?

ETS is a well-known manufacturer of high-performance intercoolers and charge-air systems for turbocharged Mitsubishi vehicles, including the Eclipse GST, GSX, and the DSM (Diamond Star Motors) family. Their systems are engineered to replace the restrictive factory side-mount intercooler with a much larger front-mount unit. A full ETS intercooler system includes the intercooler core, aluminum piping, silicone couplers, and all necessary hardware. The primary benefit is a dramatic drop in intake air temperature, which allows the engine to run more timing and boost pressure without detonation. This translates to more consistent power, especially during repeated pulls or high-ambient-temperature driving.

Complete Cost Breakdown

1. Intercooler Core

The heart of the upgrade is the intercooler core itself. ETS offers several core sizes and configurations for the Eclipse GST. Prices vary based on core thickness (typically 3.5 to 5 inches), end-tank design, and whether you choose a race or street version.

  • Street Core (3.5-inch thick): $600 – $700 – Ideal for bolt-on turbo upgrades up to about 450 whp. Retains factory AC and power steering lines with minor trimming.
  • Race Core (4.5 to 5-inch thick): $700 – $900 – Designed for high-boost applications (500+ whp). Requires more bumper support trimming and may require AC relocation.
  • Short Route vs. Long Route: Short-route piping is now standard on most full kits. It reduces airflow path length and improves throttle response. Expect to pay a slight premium (around $50-100) over long-route designs.

Pro tip: ETS cores are cast from 6061 aluminum and pressure-tested. Some enthusiasts choose used units from forums but be wary of bent fins or internal oil contamination. A new core with a warranty (usually 1 year) is a safer investment for a build you plan to keep long-term.

2. Piping Kit and Routing

The piping kit connects the turbocharger compressor outlet to the intercooler inlet, and the intercooler outlet to the throttle body. ETS kits use mandrel-bent 2.5-inch or 3-inch aluminum piping, depending on your turbo size. The kit typically includes a blow-off valve (BOV) flange and optional recirculation fitting for the 2G Eclipse GST.

  • Standard piping kit (2.5-inch): $200 – $250 – Suitable for stock frame turbos like the T25 or 14B, up to roughly 350 whp.
  • 3-inch piping kit (high-flow): $250 – $350 – Necessary for larger turbos (16G, 20G, or Garrett variants). Allows for higher CFM flow without restriction.
  • BOV adapter or flange: Often included, but if you are running an aftermarket blow-off valve (e.g., GReddy, Tial), you may need a separate weld-on flange ($15 – $30).

Piping finishes vary: polished, wrinkle black, or raw aluminum. Polished adds about $50-100 to the kit price but resists corrosion and looks cleaner under the bumper. Raw aluminum is cheaper but will oxidize over time.

3. Silicone Hoses and Clamps

High-quality silicone couplers are critical to prevent boost leaks. ETS kits include reinforced silicone hoses, typically 4-ply or 5-ply, with a heat rating of up to 350°F. The kit will also come with heavy-duty T-bolt clamps. However, if you are mixing components or need extra couplers for a custom route, budget for replacements.

  • Complete silicone hose set (ETS-specific): $100 – $150 – Includes 4 to 6 couplers in standard diameters (2.5”, 3”, or reducer couplers).
  • T-bolt clamps (set of 10): $20 – $40 – Upgrading from standard worm-gear clamps is recommended for high-boost setups above 20 psi. T-bolts provide even clamping force without deforming silicone.
  • Optional: Silicone vacuum line kit: $20 – $30 – For routing the turbo boost reference line to the wastegate and BOV. ETS does not always include these, so factor them in if you are starting from scratch.

Note on couplers: Cheap silicone can collapse under vacuum or burst under pressure. Stick with recognized brands like ETS, Vibrant, or HPS. A boost leak test after installation is strongly recommended.

4. Labor Costs

Installing a full ETS intercooler system on a 2G Eclipse GST is considered a moderately difficult DIY job. The factory side-mount intercooler is located behind the passenger-side wheel well liner and requires removing multiple components. If you are paying a shop, labor hours vary:

  • DIY assumption: 4-6 hours for a first-time installer, 2-3 hours for an experienced DSM mechanic.
  • Shop labor (general automotive): $150 – $300 – Based on 3-4 hours at $50-$75 per hour. Performance shops may charge $100/hour, raising cost to $300-$400.
  • Additional labor if AC or power steering lines need moving: +$100 – $200 – Not always required, but on some Eclipse GSTs with AC, the factory hard lines conflict with the thicker race core. A shop might relocate the condenser or use shorter fittings.

Real-world advice: Many Eclipse owners perform this upgrade themselves to save money and learn the car. However, if you lack tools (e.g., an angle grinder for cutting the bumper support beam), renting or buying them adds $50-$100 to the DIY route.

5. Additional and Hidden Costs

Beyond the basic intercooler system, you must consider ancillary modifications and tuning. A larger intercooler increases the volume of the charge air system, which can alter boost control and require a tune to take full advantage of the cooler intake air.

  • Custom Tuning (ECU reflash or chip): $200 – $500 – On an Eclipse GST with a 2G ECU, you can install an EPROM chip (like a Dsmlink chip or a flashable ECU). A remote tune through a service like ECMtuning or a local dyno tune will cost $250-$600. Without tuning, you may not see the full benefit and risk leaning out the mixture.
  • Aftermarket Blow-Off Valve (if not included): $50 – $200 – Many ETS kits come with a recirculation flange but no BOV. A GReddy Type RS or Tial Q can be added. Recirculating is required for the stock 2G MAS setup; venting to atmosphere will cause rich stumbles.
  • Fuel system upgrade (optional but recommended for high-boost): $150 – $400 – The stock fuel pump and injectors are sufficient for up to around 350 whp. If you plan to increase boost significantly, a Walbro 255lph fuel pump and 550cc injectors may be necessary. This adds to the total cost but is not part of the intercooler system directly.
  • Bumper support trimming tool (die grinder or saw): $30 – $80 – You will need to cut a section of the front bumper crash bar (or the support beam) to clear the intercooler core. A reciprocating saw with a metal blade or a die grinder works. If you cannot borrow one, add this cost.
  • Relocation brackets / AC line modification: $20 – $50 – For race cores, you may need to bend or replace AC lines. A local shop can make new lines for $80-$150.

Total Estimated Cost Range

Based on the breakdown, here is the all-in investment for a full ETS intercooler system on your Eclipse GST:

  • Budget (street core, used parts, DIY with basic tune): $1,200 – $1,500
  • Mainstream (race core, new piping, shop labor, proper tune): $1,700 – $2,200
  • All-out (large race core, 3-inch piping, ported BOV, dyno tune, fuel system): $2,500 – $3,000

Regarding your original estimate: The prior low-end of $1,370 is realistic for a partial do-it-yourself build with a used core. The high-end of $2,200 covers a new race kit, professional labor, and a basic tune. Adjust these numbers based on your region and specific turbo setup.

Performance Benefits and ROI

What do you get for this investment? On a stock-turbo Eclipse GST, a full ETS intercooler system can lower intake air temperatures (IAT) by 30-50°F, reduce the risk of knock, and allow the ECU to advance timing. Typical power gains are 10-20 whp with no other changes, purely from more consistent air density. When combined with a boost controller and tune, 30-50 whp gains are common. The system also improves throttle response because the short-route piping reduces volume compared to the convoluted stock side-mount plumbing.

For owners upgrading to a 16G or larger turbo, the ETS intercooler is nearly mandatory to handle the additional airflow. The stock side-mount becomes a bottleneck above 300 whp. In that context, the $1,200-$2,200 is a sensible upgrade that protects your engine investment.

Installation Considerations

Installing a front-mount intercooler on a 2G Eclipse GST requires cutting a hole in the passenger-side frame rail support. This is irreversible. Measure twice, cut once. Many guides on DSM forums (like dsmtuners.com) provide templates for the proper cut location. You will also need to remove the front bumper and radiator support panel. Expect to spend a full day if working in a driveway with basic hand tools.

  • Tools needed: Socket set (10mm, 12mm, 14mm), angle grinder with cutoff wheel, drill with step bit (for mounting brackets), jack stands, and a boost leak tester.
  • Potential complications: The intercooler piping may interfere with the A/C accumulator or the cruise control module. Relocating the cruise control bracket ($10 for a simple L-bracket) is common. Some owners delete cruise control entirely.

Comparing ETS to Other Brands

ETS is not the only option for the Eclipse GST. Popular alternatives include:

  • Punishment Racing: Similar quality, slightly lower cost ($500-$650 for core + piping). Their piping uses fewer pieces but may require more trimming.
  • VRSF (Vishnu Racing): Budget-friendly at $400-$550 for a complete kit. Tends to have heavier cores and thicker wall piping. Works fine for street use but may restrict flow at high boost.
  • Custom (parts bin): Mixing a Garrett core with custom piping can be cheaper ($300-$500) but requires fabrication skills.

ETS cores are generally considered the gold standard for DSM intercoolers because of their superior fin density and pressure drop testing. If your budget is tight, a used ETS core from a part-out is often worth the search.

Frequently Asked Questions

Will an ETS intercooler fit a 1G Eclipse GST or TSi?

Yes, but the 1G chassis has a narrower front opening. You will need the specific 1G short-route kit from ETS (piping is different around the radiator). Expect similar pricing.

Do I need to upgrade my radiator?

Not immediately. The intercooler sits in front of the radiator, so there is a slight impact on cooling airflow. On a street car, the stock aluminum radiator is sufficient. For track use, consider a Mishimoto or Koyo aluminum radiator later.

How much boost can an ETS intercooler support?

The race core (4.5-inch) can handle over 30 psi and 700+ whp. The street core is comfortable up to 25 psi and 500 whp. The limiting factor is usually the piping or clamps, not the core itself.

Will I pass emissions with a front-mount intercooler?

Generally yes, since it does not affect tailpipe emissions directly. However, if you remove the A/C for clearance, that may be visual inspection issue in some states. The intercooler itself is not a smog problem.

Final Verdict

Upgrading to a full ETS intercooler system on your Eclipse GST is a high-value modification that future-proofs your engine for increased boost and power. The total cost ranges from approximately $1,200 to $2,500 depending on your choices of core size, labor, and tuning. While it is not the cheapest single mod, the combination of improved IATs, reduced knock, and support for larger turbos makes it a cornerstone of any serious DSM build. Budget realistically, shop around for package deals (ETS often offers combo pricing), and do not skip the tuning step. Your 4G63 will thank you.

For further reading, check out ETS official DSM intercooler page for current pricing, or visit DSM Tuners forums for installation tips and real-world feedback.