Greddy / Trust: The Intercooler Giant That Redefined Japanese Tuning

Greddy (スタートラスト Trust Co., Ltd. in Japan) is, next to HKS, the most commercially successful Japanese aftermarket tuning company in history. Founded in 1977 as "Trust" (トラスト), the company later adopted the Greddy brand name for international markets. Greddy's specialty is forced induction support products — intercoolers, piping kits, blow-off valves, intake manifolds, and boost controllers — and for many tuners in the 1990s and 2000s, "Greddy" and "intercooler" were effectively synonymous.

The Trust Origin (1977)

Trust was founded in 1977 in Ibaraki Prefecture, Japan, initially as an engineering consultancy for Toyota Racing Development (TRD). The founders had deep ties to Toyota's motorsport program and brought industrial design experience from Toyota's research labs. In the early 1980s, Trust began manufacturing aftermarket parts under their own brand, with intercoolers as their flagship product.

Why intercoolers? Because in the early 1980s, most factory turbocharged Japanese cars came with small, restrictive intercoolers that were the main bottleneck on performance. Trust's air-to-air intercooler designs were larger, more efficient, and allowed tuners to run significantly more boost without worrying about charge temperature. This was a game-changer for the Japanese tuning scene.

The "Greddy" brand name was adopted for the USA and European markets in the late 1980s. The full name "Greddy" is short for "GReat DeDicated Yokohama" or possibly "GReddy" as a play on the word "greedy" — historical accounts differ. The name became internationally synonymous with Japanese tuning parts.

Signature Products

Greddy Intercoolers

The product line that built the company. Greddy intercoolers are available in multiple sizes and configurations:

• Type 23 — The iconic small-diameter core intercooler, common on modest builds
• Type 24 — Slightly larger, balanced for street/strip
• Type 25 — The "standard" large-core Greddy intercooler, the most commonly-installed of the line
• V-Mount Type — Vertically-mounted intercoolers for front-engine, rear-radiator configurations (popular on Mazda RX-7 FD and Skyline GT-R builds)

All Greddy intercoolers feature cast aluminum end tanks (not welded), multi-pass tube-and-fin cores, and precision-bent aluminum piping kits. The quality is Japanese, and prices reflect it.

Greddy Profec B Spec II Boost Controller

The most popular electronic boost controller in Japanese tuning history. Introduced in 1995, the Profec B Spec II replaced clunky mechanical bleed valves with an electronic solenoid-driven system that allowed precise boost target setting and switching between high/low boost maps. A new Profec 2 was released in the early 2000s. Still in production today under the Profec OLED name.

Greddy Type S Blow-Off Valves

The Greddy Type S BOV is arguably the most recognizable aftermarket blow-off valve ever made. Anodized gold or black, with a characteristic "pssshhhhh" sound that became the audio signature of modified Japanese cars in the 2000s. Mounted on countless magazine cover cars.

Greddy Turbo Kits

Greddy assembled and sold complete turbo kits for popular Japanese cars:

• Turbo Kits for SR20DET (S13/S14/S15) — Upgraded T25/T28 turbos with Greddy manifolds
• Turbo Kits for RB26DETT (R32/R33/R34 GT-R) — Larger T51R or T78 turbos with Greddy manifolds
• Turbo Kits for 2JZ-GTE (Supra MK4) — T88 or T78 single-turbo conversion kits

These kits were turnkey installations — everything you need to swap from factory turbos to a larger single or twin setup.

Greddy T78 and T88 Turbochargers

Greddy-branded versions of large Mitsubishi Heavy Industries turbos. The T78 and T88 are single-turbo upgrades used in many high-HP Japanese builds. Capable of supporting 700-1,200 HP depending on configuration.

Greddy e-Manage Ultimate ECU

A piggyback engine management system. The e-Manage allowed tuners to modify factory ECU signals without replacing the factory ECU — adding ignition advance, fuel enrichment, and boost control corrections. For street-driven cars with factory ECU constraints, the e-Manage was (and remains) an attractive option. Standalone tuners often prefer dedicated ECUs like AEM or Haltech for high-HP builds.

Motorsport Involvement

Greddy/Trust has sponsored and supplied parts to numerous race teams:

• All-Japan Grand Touring Car Championship (JGTC) — 1990s-2000s cars running Greddy intercoolers and turbos
• Super GT — Continued involvement with Greddy-supported entries
• Drag Racing — Multiple 6-second and 7-second Japanese drag cars running Greddy components
• Drift — Many D1 Grand Prix cars run Greddy intercooler piping and BOVs
• Time Attack — Greddy-supported cars at Tsukuba, Suzuka, and international venues

Greddy also sponsored the Greddy Trust Racing Team in various Japanese touring car championships through the 1990s.

Greddy Today

Greddy USA operates as a separate entity from the Japanese Trust company, based in Irvine, California. Their primary business is distributing Trust-manufactured Greddy parts to the North American market, but they also provide engineering support for tuners and race teams.

The Trust brand continues to manufacture intercoolers, piping kits, and electronic management systems in Japan. Their product range has expanded to include European and American car fitments, but the core business remains Japanese performance cars.

Why Greddy Matters

Greddy transformed what was possible for budget-minded Japanese tuners. In the 1990s, building a 500 HP Supra or GT-R required custom fabrication — custom intercoolers, custom piping, custom tuning. Greddy sold turn-key kits that allowed backyard tuners to bolt on OEM-quality performance parts without needing a machine shop or fabrication equipment. This democratized Japanese tuning.

Today, when you see a modified 2JZ-GTE with a Greddy Type S blow-off valve, a Greddy intercooler, and Greddy piping, you're looking at a configuration that defined Japanese tuning for an entire generation. The gold and black Greddy logo is as iconic as the HKS blue, and the company remains a pillar of the global Japanese aftermarket performance scene.