G-Sport Gen2 UHO EPA Compliant Catalytic Converter Core - 4.500" Body x 4.000" Long (85200)

Also available: HO 4.000" Core (50200) | UHO+ 5.000" Core (85500) | Fabricator 6-Pack (685200)

850HP OF EPA-COMPLIANT FLOW, CORE ONLY — G-SPORT GEN2 ADVANCED UHO CORE

The G-Sport Gen2 Advanced UHO (Ultra High Output) Catalytic Converter Core (85200) packs an 850hp-per-core rating into a bare 4.500" OD x 4.000" long canister built for full custom integration. The larger body carries substantially more substrate cross-section than the HO core — total flow area comparable on paper to an open 3.000" straight pipe — so high-output builds keep their power and their emissions compliance at the same time.

This is the catalytic core only — transition cones are sold separately. The matching cone for a 4.500" OD body is the 3.000" Transition Cone (94530), or you can fabricate your own transitions.

The GEN2 Advanced series pairs GESi's proven S-Wound metallic substrate in a 400 CPSI cell count with their latest proprietary precious-metal coating, developed for the advanced OBD monitoring strategies on 2017 and newer vehicles — the combination that prevents catalyst-related check engine lights on late-model platforms. Gen2 is also fully compatible with earlier model years, making it the safe choice when in doubt.

FEATURES

• Rated up to 850hp per core — 4.500" body for maximum substrate flow area
• Core-only format for full custom exhaust integration — weld directly into your system
• 400 CPSI S-Wound metallic substrate with proprietary GEN2 wash coat for 2017+ emissions monitoring
• Nickel-lined, furnace-brazed substrate locked to its stainless mantle — will not telescope or fail under boost
• 300 Series stainless steel construction; withstands exhaust temperature spikes up to 1,600°F
• EPA compliant — third-party lab tested (not CARB certified; not for use on emissions-controlled vehicles in California)

SPECIFICATIONS

• Sold As: Catalytic core only (transition cones sold separately)
• Body Diameter: 4.500" OD
• Overall Length: 4.000" (±0.125")
• Cell Count: 400 CPSI
• HP Rating: up to 850hp per core (per exhaust bank)
• Substrate: S-Wound metallic, furnace-brazed
• Material: 300 Series stainless steel
• EPA Compliant: Yes (not CARB certified)
• Weight: 3.24 lbs
• Connection: Welding Required

PERFORMANCE

In instrumented dyno testing with pressure probes upstream and downstream of the substrate, a properly sized G-Sport high-flow catalytic converter produced horsepower and torque curves identical to a straight pipe, with no measurable pressure drop across the core. Emissions reduction runs up to 99% for carbon monoxide, 98% for nitrogen oxides, and 95% for hydrocarbons.

APPLICATIONS & FITMENT

Choose the Gen2 UHO core for custom builds between 500hp and 850hp per exhaust bank. Past 850hp, step up to the UHO+ 5.000" (85500, 1,000hp) or UHOX 6.000" (85600, 1,200hp). Prefer a weld-ready converter with cones already installed? See the Gen2 UHO 3.000" (85230) and Gen2 UHO 4.000" (85240) assemblies. For 2016 and older vehicles, the Gen1 UHO Core (85002) offers the same 850hp rating with a higher-flow 300 CPSI substrate.

For the full selection guide, see Understanding the G-Sport Catalytic Converter Lineup and our G-Sport FAQ.

INSTALLATION NOTES

This core welds into your system via the 94530 transition cone or custom-fabricated transitions. For best catalyst light-off and CEL prevention, install it as close to the OEM converter location as practical — on custom systems, within 8"–24" of the turbo outlet or header collector. In dual-bank systems, run the same core model on both banks; mixing generations or sizes between banks can cause uneven backpressure and inconsistent O2 readings. Full best practices, common mistakes, and a pre-flight checklist are in our G-Sport Installation Guidelines.

Not sure which generation or output tier your build needs? Email us at support@aceraceparts.com with your platform, power goal, and tubing size and we will point you to the right part.