VGT vs Non-VGT Turbo for the 6.7 Powerstroke
Search for a 6.7 Powerstroke turbo upgrade and you will find two very different kinds of product: drop-in variable geometry (VGT) turbos that replace the factory unit in place, and non-VGT kits that swap in a fixed geometry turbo, often an S300 or S400. They solve different problems. Here is how to choose.
Quick answer: If the truck tows, daily drives or uses the exhaust brake, a drop-in VGT upgrade is usually the better choice. A non-VGT conversion makes sense for dedicated performance or competition trucks that no longer need factory spool, the exhaust brake or factory emissions equipment.
What the Vanes Do for You
The factory 2017–2019 turbo has a ring of movable vanes around the turbine wheel. That one mechanism handles three jobs:
- Low-speed spool. Closed vanes speed up exhaust gas into the turbine, so a large turbo responds like a small one off idle.
- Boost control. Opening the vanes at high load limits boost without a wastegate.
- Exhaust braking. Partly closing the vanes builds back pressure, which is how the factory exhaust brake works.
A fixed geometry turbo has none of that. Its turbine housing has one size of opening, chosen once, as a compromise between spool and top-end flow.
Side by Side
| Drop-in VGT | Non-VGT (fixed geometry) conversion | |
|---|---|---|
| Spool | Close to factory | Depends on sizing; usually slower off idle |
| Exhaust brake | Factory VGT control and exhaust brake retained | Factory exhaust brake function is lost |
| Installation | Factory location and plumbing | Kit or fabrication: pedestal, piping, oil drain, often a wastegate |
| Tuning | Required for rated power | Required; calibration must account for no vanes |
| Factory emissions equipment | Can stay in place | Not compatible |
| Sustained towing | Strong | Possible, but heavier trucks miss the brake and low-speed response |
| Peak power ceiling | High for a drop-in | Higher, with the right turbo and fuel |
| Long-term reliability | Vanes need clean oil and regular use | No vanes to stick; fewer moving parts |
When a Drop-In VGT Makes Sense
- The truck pulls fifth wheels, goosenecks or equipment trailers
- You rely on the exhaust brake on grades
- It is a daily driver and you want factory-like manners
- You want to keep the factory emissions equipment
The TNT 63.5/62 drop-in is built for this use on 2017–2019 F-250 to F-550 trucks, keeps the factory exhaust brake, and has a 63.5mm (2.50") 6+6 compressor and 10-blade mixed-flow turbine. It is rated to 650 HP with factory emissions equipment in place and up to 750 HP in off-road competition builds, both with tuning.
When a Non-VGT Conversion Makes Sense
- The truck is a dedicated performance, sled pull or drag build
- Power goals are past what any drop-in supports
- You are prepared for the fabrication and tuning work
- Losing the exhaust brake does not matter for how the truck is used
If that is your build, see S300 Turbo for Power Stroke and S400 Turbo for Power Stroke for sizing and the flange, clamp and drain hardware a conversion needs.
For the full upgrade picture, see the 6.7 Powerstroke Turbo Upgrades guide.
Frequently Asked Questions
Do I lose the exhaust brake with a non-VGT turbo on a 6.7 Powerstroke?
Yes. The factory exhaust brake works by closing the turbo's variable vanes. A fixed geometry turbo has no vanes, so that function is lost.
Is a non-VGT turbo more reliable?
It has fewer moving parts, so there are no vanes to stick. Reliability in practice depends far more on correct sizing, tuning, oil supply and drain routing.
Is a VGT drop-in good enough for 650 HP?
Yes, with the right turbo. The TNT 63.5/62 is rated to 650 HP with factory emissions equipment in place and up to 750 HP in off-road competition builds, both with tuning.
Can I tow with a non-VGT turbo?
Yes, but you lose the factory exhaust brake and usually some low-speed response, which matters most on heavy trailers and steep grades.
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.