At FASS Motorsports in Washington, Missouri, we’re proud to offer some of the best diesel tuning in the country by partnering with Kory Willis and PPEI.
If you’re looking for professional, proven, diesel tuning for your Cummins, Duramax, or Powerstroke, we've got your back.
Before we go any further, let’s make one thing perfectly clear:
FASS Motorsports and PPEI DO NOT offer “delete” tuning of any kind. Tuning that defeats or eliminates emissions equipment is still federally illegal as of 12/8/2025. Please don't ask.
Who Is PPEI & Kory Willis?
PPEI, led by legendary tuner Kory Willis, is one of the most trusted and respected diesel tuning companies in the world. For years, PPEI has been the go-to name for:
- Clean, safe power
- Exceptional drivability
- Reliable towing performance
- Competition-level diesel tuning
PPEI tuning is used on everything from daily drivers and tow rigs to full-blown race trucks. Their reputation is built on doing things the right way — safely, legally, and reliably.
What Type of Tuning Does FASS Motorsports Offer?
Through our partnership with PPEI, FASS Motorsports offers two types of diesel tuning:
- Pre-emissions tuning (older model trucks that were never equipped with EGR/DPF/DEF)
- Emissions-intact tuning for modern diesel trucks that retain all factory emissions equipment
That means:
- No emissions removal
- No DPF deletes
- No EGR delete tuning
- No SCR or DEF removal tuning
What Is Pre-Emissions Tuning?
Pre-emissions trucks are diesel vehicles that came from the factory without modern emissions systems like DPF, SCR, and DEF. These typically include:
- 2007 and older Duramax trucks
- 2007 and older Cummins trucks
- Older Powerstroke platforms (such as 6.0L and earlier)
For these trucks, PPEI provides incredibly clean, powerful tuning that improves:
- Throttle response
- Horsepower and torque
- Towing performance
- Fuel economy (when driven responsibly)
All without compromising reliability.
What Is Emissions-Intact Tuning?
Emissions-intact tuning means your truck retains:
- DPF
- EGR
- SCR system
- DEF system
- All factory sensors and monitoring systems
PPEI’s emissions-intact tuning is designed to:
- Increase power safely
- Improve towing performance
- Enhance drivability
- Maintain long-term reliability
- Keep your truck compliant with emissions regulations
This is the legal way to tune modern diesel trucks — and it’s the only type of tuning we offer at FASS Motorsports.
Why We Partnered With PPEI
We chose PPEI because their values align with ours:
- Safety-first tuning
- No shortcuts
- No sketchy, stolen files
- U.S.A-based company and customer support
- Real-world, dyno proven performance
When we tune a truck at FASS Motorsports using PPEI software, we’re confident that customer is getting:
- A truck that drives better
- A truck that tows stronger
- A truck that lasts longer
- A truck that stays legal
Why Emissions-Delete Tuning Is NOT Offered
This cannot be stated clearly enough:
FASS Motorsports and PPEI do NOT offer delete tuning. It's still federally illegal, and we're not interested in fines or jail time.
The simple fact is, delete tuning can create:
- Massive legal liability for the shop/company offering the tunes
- Registration problems in emissions-tested counties
- Inspection failures
- Warranty issues
If you’re searching for delete tuning, we are not the shop for you.
Local PPEI Tuning in Washington, Missouri
FASS Motorsports proudly offers local PPEI diesel tuning for customers throughout:
- Washington, MO
- Franklin County
- St. Louis Metro Area
- And surrounding regions
By working with us locally, you get:
- In-person support
- Professional setup and configuration
- Verified tuning files directly from PPEI
- Expert diesel advice from our team
FASS Motorsports: Your Trusted Diesel Performance Shop
From FASS Fuel Systems and suspension upgrades to safe, emissions-intact tuning, FASS Motorsports exists to help diesel owners build trucks the right way.
👉 Visit FASSMotorsports.com
👉 Stop by our Washington, MO showroom to talk tuning with our team
Have Questions? We're here to help.
- Phone: (636) 429-7020
- Email: info@fassmotorsports.com
FASS Motorsports
25 Town and Country Drive
Washington, MO 63090
