HE300VG & HE400VG VGT Turbos for 6.7L Cummins

HE300VG / HE400VG VGT Turbos

HE300VG & HE400VG VGT Turbos for 6.7L Cummins

OEM-Style Variable Geometry Technology with Performance Upgrades

HE300VG and HE400VG turbos are variable geometry (VGT) upgrades designed specifically for 2007.5-2024 6.7L Cummins engines.

Unlike fixed-geometry turbos, VGTs use movable vanes to optimize boost across the entire RPM range—delivering quick spool at low RPM and strong top-end flow. Perfect for daily drivers, work trucks, and towing applications where maintaining emissions equipment and factory-like drivability is important.

Variable Geometry

Adjustable vanes optimize boost across RPM range

Emissions Friendly

Works with EGR and DPF systems (where required)

Factory Features

Maintains tow/haul mode, exhaust brake, engine braking

Drop-In Fitment

Direct replacement for stock 6.7L VGT turbos

Key Differences: HE300VG is smaller frame (better spool, 350-450 HP), HE400VG is larger frame (more airflow, 450-550+ HP).

HE300VG & HE400VG VGT Turbo FAQs

VGT = Variable Geometry Turbo. It has movable vanes inside the turbine housing that adjust based on engine load and RPM.

How VGT works:

Low RPM/light load: Vanes close down, creating smaller effective turbine area → faster spool, quick boost response
High RPM/heavy load: Vanes open up, creating larger turbine area → maximum airflow, prevents over-boost
Result: Best of both worlds—responsive like a small turbo, flows like a large turbo

Fixed-geometry turbo (S300, S400):

Single fixed turbine housing size
Compromise between spool and airflow
Either spools quick (but chokes at high RPM) or flows great (but lags at low RPM)

Why VGT for 6.7L Cummins? Factory uses VGT for emissions control, engine braking, and drivability. Upgrading to HE300VG or HE400VG gives you more power while keeping those factory features intact.

Yes, typically 100-175°F cooler than stock when towing similar loads.

Why VGT upgrades help with EGTs:

Better airflow efficiency: Upgraded turbine and compressor wheels flow more air at the same boost level
Optimized vane positioning: Custom tuning positions vanes for best efficiency under load
Less boost needed: More efficient turbo requires less boost pressure to make the same power = cooler combustion

Real-world example:

Stock HE351VE: 1,350°F towing 18k lbs up 6% grade
HE400VG upgrade: 1,175-1,225°F same load, same grade
Result: 125-175°F cooler, less stress, more confidence

Compare to fixed-geometry turbos:

S300 singles: Similar EGT reduction (150-200°F) but lose VGT features
Compound systems: Better EGT reduction (200-300°F) but much higher cost and complexity

For many 6.7L Cummins owners, VGT upgrades offer the best balance: significant EGT improvement while keeping all factory functionality.

HE300VG (Smaller Frame):

Best for: Daily drivers, moderate towing (10-15k lbs), 350-450 HP builds
Pros: Quickest spool, best low-end response, excellent street manners, maintains great fuel economy
Cons: Limited to ~450 HP before running out of airflow
Ideal user: Owner who wants better performance than stock but prioritizes drivability and daily comfort

HE400VG (Larger Frame):

Best for: Heavy towing (15-25k lbs), 450-550+ HP builds, performance-focused trucks
Pros: More top-end airflow, supports higher power, better for sustained heavy loads
Cons: Slightly more lag than HE300VG (still much better than fixed turbos), needs more supporting mods to shine
Ideal user: Hot-shot driver, heavy RV tower, or performance enthusiast wanting 500+ HP with VGT benefits

Quick decision guide:

Stock to 450 HP, daily driver focus → HE300VG
450-550+ HP, heavy towing focus → HE400VG

Yes. HE300VG and HE400VG VGT turbos are widely used in towing and street-driven diesel applications because they provide fast response at low RPM while still flowing enough air for higher boost under load. When properly sized and tuned, these VGT turbos deliver smooth drivability, strong midrange torque, and reliable performance for daily driving, towing, and performance builds.

Yes—this is one of the main advantages of VGT turbos.

HE300VG and HE400VG turbos are designed to work with factory emissions systems:

EGR (Exhaust Gas Recirculation): VGT controls backpressure needed for EGR function. Maintains proper EGR flow rates.
DPF (Diesel Particulate Filter): VGT helps generate heat needed for DPF regeneration cycles. Keeps regen functioning properly.
Emissions sensors: Factory sensors (boost, exhaust temp, etc.) work normally with VGT upgrades

Important for emissions-regulated states:

If you live in California or states with strict diesel emissions laws, VGT turbos allow performance gains while staying street-legal
Deleting emissions equipment may be illegal for on-road use in your area—check local laws

Note: While VGTs work with emissions equipment, you'll need tuning that's calibrated for emissions-on operation. Work with tuners familiar with emissions-compliant tuning for best results.

HE300VG:

Realistic power range: 375-450 HP
With aggressive tuning and supporting mods: Up to 475 HP (pushing the limit)
Sweet spot: 400-425 HP for best balance of power and drivability

HE400VG:

Realistic power range: 450-550 HP
With full supporting mods: 550-600 HP
Sweet spot: 475-525 HP for excellent towing and street performance

Supporting mods needed for these power levels:

Essential: Tuning matched to VGT (critical—off-the-shelf tunes may not be optimized)
Recommended for 450+ HP: Upgraded intercooler, lift pump, 4" exhaust
Required for 500+ HP: Injector upgrades, possibly CP3 pump work, transmission upgrades

VGT turbos aren't designed for extreme horsepower (700+ HP). For those goals, see our S400 Single Turbos or Compound Systems.

HE300VG / HE400VG VGT Turbos