Garrett PowerMax on a Gen 3 Raptor: How Full Race and MPT Finally Brought This Setup to Life

This project has been a long time coming. Years, honestly. Long before this 2021 Gen 3 Raptor ever rolled into the shop, we had already proven twice, that Gen 2 Garrett PowerMax turbos could work on a Gen 3 platform.

The problem was the wiring.
Every other tuner who tried ended up stuck at the same point: the wastegates.
The signals don’t match, the connectors don’t match, and the truck loses its mind the moment you fire it up.

But after working through two nearly identical builds, and after a ton of back-and-forth testing and verification with Geoff at Full Race, we knew the solution. The only missing piece was making the process plug and play so anyone could install it without cutting, splicing, or rerouting wires.

So Full Race made the call:
Buy a Gen 3 Raptor, build it properly in Arizona, and ship it clear across the country to MPT in Florida for final development and tuning.

This truck is the result of that plan.

Truck Arrival & Pre-Dyno Inspection

The truck showed up wearing the full package:

• Garrett PowerMax Stage 2 turbos (originally for Gen 2 17-20 Raptor)

• Full Race’s prototype wastegate adapter harness

• SPD downpipes

• Supporting bolt-ons and hardware already installed

A quick walk-round revealed somebody had fun with it before it reached us, dirt on the body and the lower panels made it pretty clear it had been “tested” at some point between Arizona and the holding facility.

No big deal.
The important part was confirming the turbo install, the wastegate adapters, and the downpipe fitment before powering up.

Initial Startup: Wastegate Codes 

The moment the truck fired up, the dash lit up:
Check engine light.
Wrench light.
Exactly what you’d expect if one side of the wastegate system wasn’t talking to the truck correctly.

Pulling codes with the SCT showed:

• P25B4 – Wastegate A Stuck Closed

That’s the one that forces limited power, reduced boost, and the wrench icon.

Here’s the thing though — we knew this setup worked.
We had already:

1. Run this turbo combo twice

2. Proved the wiring order

3. Worked with Geoff at Full Race to design the correct adapter

So instead of guessing, we simply compared both sides, verified the issue, swapped in the proper adapter orientation, and within minutes:

• Both wastegates responded

• All DTCs cleared

• The truck was finally acting the way it should

This right here is why Full Race decided to buy a whole truck for this project. No more trial and error. No more hoping someone pins it correctly. The goal was a repeatable, reliable, bolt-on solution, and this was the final validation step.

Downpipe Break-In & Road Prep

Before heading to the dyno, SPD’s downpipe break-in procedure was completed. The truck warmed up, cycled through the steps, and everything looked stable enough to begin baseline testing.

Baseline Testing

The goal was to compare four stages:

1. Stock turbos on stock tune (previous dyno in Arizona)

2. PowerMax turbos on stock tune

3. MPT 91 PR-X tune

4. MPT 93 PR-X and E50 PR-X tunes

This tells us:

• How much spool changes with bigger turbos

• How much airflow increases up top

• How much headroom exists once tuning begins

Result: Stock vs Stock-With-Mods

PowerMax turbos are larger, so spool naturally shifts about 500–700 RPM later, but the truck immediately showed stronger top-end airflow, even on the stock tune.

91 PR-X Tune Results

This truck came from Arizona still running ACN 91, and surprisingly, even on this lower grade fuel, the setup worked extremely well.

91 PR-X Output:

• 557 HP

• 548 TQ

That’s on low-grade 91 with boost still limited for engine safety.

93 PR-X Tune Results

Once we added fresh 93, the truck picked up right where it should — about 3–5 percent more than 91, with all torque caps still in place.

Smooth, predictable, and exactly the way a properly controlled PowerMax setup should behave.

E50 PR-X Tune Results: The Big One

With a blend of E85 in the tank, the truck was ready for the real test.

E50 PR-X Output:

• 690.4 HP

• 632.9 TQ

This is on:

• A stock engine

• 73k miles

• Conservative torque limits

• Safe boost levels

The system has well over 700 wheel horsepower in it if pushed harder, but that crosses into the “time bomb” territory on a stock long block.

The important takeaway is this:
The setup works, and it works extremely well when the wastegate strategy is done correctly.

Why This Project Matters

This wasn't just another turbo install.
This was the final step in turning something that previously only worked with hand-built wiring fixes into a full plug-and-play kit.

• Others tried.

• Others threw in the towel.

• Full Race and MPT didn’t.

We had real data from two prior builds. We had the wiring logic already proven. We had the testing, the dyno time, and the experience to finally wrap this up into something anyone can install.

Full Race buying a truck and sending it cross-country just to make this kit right says everything about the commitment behind this project.

And now the results speak for themselves. Check out the full kit here:

https://morepowertuning.com/products/full-race-a0227a