The TNT376 76mm T4 is a journal bearing turbocharger built to order in Canada, featuring billet compressor and turbine wheels machined from forged 2618 aluminum. It is the top of the 300 frame in practical terms — a 76mm compressor in a 300-frame centre section, paired with the largest turbine wheel the frame offers.

Key Specs

• 76mm x 102mm compressor wheel, billet, journal bearing
• Maximum 1,210 HP (crank)
• 360-degree thrust bearing with increased thrust surface area
• Optimized compressor stage aerodynamics
• 4" inlet, 2.5" outlet compressor housing
• Boss cast and pre-tapped for an M6x0.5 rotor speed sensor
• Standard 1/8" NPT pressure port
• 82x75 turbine wheel, T4 flange (.88 A/R open or .91 A/R divided)
• Interchangeable with existing turbine housings for upgradability

The TNT376 is offered with the 82x75 turbine only. At this compressor size a smaller turbine wheel would become the limiting restriction, so the pairing is fixed rather than optional.

⚠️ TNT376 Is Not a TNT476

Both use a 76mm (2.99") compressor. Nothing else carries over. This is the single most common ordering error on this frame:

The 4.25" and 4.62" marmon flanges are 0.37" apart — indistinguishable in a marketplace photo, identical when a forum post says only "marmon," and they will not clamp together. Measure your turbine housing outlet before ordering. See the S376 guide for the full comparison.

Replaces / Cross-Reference

The TNT376 is a direct bolt-on replacement for S375 and S376 turbochargers and other 76mm 300-frame units:

• Turbine inlet: T4 bolt pattern — fits your existing T4 manifold
• Turbine discharge: 4.25" marmon — 4" downpipe recommended at this size
• Compressor discharge: v-band, sized to your charge pipe
• Oil drain: 50mm (1.97") bolt centre — 12AN. This is not the size to economise on oil return.

Full model mapping: S300 replacement cross-reference.

What the Build Needs at This Size

The TNT376 sits at the top of its frame, and everything around it has to be sorted. A 76mm compressor on inadequate fuelling makes less usable power than a smaller turbo on adequate fuelling. Head studs and a built transmission are prerequisites rather than options, a turbo blanket is worth having, and restricting the downpipe undoes the reason you bought a 76mm in the first place.

The 1,210 HP figure is a compressor ceiling, not a recommendation. Our practical crossover to the 400 frame sits around 820 HP — so if you are buying a TNT376 to chase a four-digit number, read the frame comparison before you commit to a manifold.

Frequently Asked Questions

What turbine wheel does the TNT376 use?

An 82x75 turbine wheel, in T4 .88 A/R open or .91 A/R divided configurations. At a 76mm compressor size a smaller turbine would become the limiting restriction, so the pairing is fixed.

How much horsepower will a TNT376 support?

Up to 1,210 crank horsepower. That is the compressor ceiling — what the 76mm wheel will support at the edge of its map — rather than a build target. Around 820 HP is where we would normally move you to a 400-frame turbo.

What is the difference between a TNT376 and a TNT476?

Both use a 76mm compressor, but the 376 is a 300-frame turbo and the 476 is 400-frame. Different centre sections, different turbine discharges — 4.25" marmon against 4.62" or 5.75" — and different oil drain bolt centres, 50mm against 50.8mm. None of the fitment hardware carries over.

Will TNT476 hardware fit a TNT376?

No. The turbine discharge flange, clamp and oil drain flange are all different. The 4.25" and 4.62" marmon flanges in particular look nearly identical but will not clamp together.

Is this turbo built to order?

Yes. Every TNT376 is built to order, assembled and balanced in Canada.

Power ratings on this page are quoted in crank horsepower (HP). Figures previously published in wheel horsepower (WHP) have been restated using our in-house tested conversion — the hardware and its capability are unchanged.