Diesel Performance
Tuning · Turbos · Fuel Systems · Exhaust · Engine Builds
Texas Hill Country's Diesel Specialists
Diesel performance is not just a service we offer — it's our passion. Based in Bulverde, TX, Hill Country Motorsports has been building some of the most powerful and reliable diesel trucks in the Texas Hill Country for over a decade.
Whether you're looking for a mild street tune that adds 100 horsepower for daily driving, or you're chasing 1,000+ HP on a full competition build, we have the knowledge, equipment, and brand relationships to make it happen right. Every build is custom — no cookie-cutter solutions.
Performance Services
Diesel Tuning & Calibration
Unlock the true potential of your diesel engine with custom ECM/TCM tuning. Our calibrations are tailored to your specific truck, fuel system, and modifications — not generic off-the-shelf tunes. We work with Calibrated Power, EZ LYNK, Edge Products, H&S Performance, and more to deliver safe, reliable power gains.
- Custom ECM/TCM calibrations
- EZ LYNK AutoAgent tuning
- Edge Products monitors & tuners
- H&S Performance tuning
- Transmission tuning & shift calibration
- DPF-on and DPF-delete configurations
Turbocharger Upgrades
From single turbo upgrades to compound twin-turbo setups, we build diesel induction systems that deliver massive power with improved reliability. We source and install turbos from Garrett, BorgWarner, KC Turbos, Midwest Turbo, and Force Inductions to match your power goals.
- Single turbo upgrades
- Compound twin-turbo systems
- Garrett & BorgWarner turbos
- KC Turbos & Midwest Turbo
- Intercooler upgrades
- Boost controller installation
Fuel System Upgrades
A strong fuel system is the foundation of every high-performance diesel build. We install lift pump systems, high-flow injectors, CP3/CP4 conversions, and fuel rails to ensure your engine gets the clean, high-pressure fuel it needs to make serious power without reliability issues.
- FASS & AirDog lift pumps
- High-flow injector upgrades
- CP3 conversion kits
- S&S Diesel fuel systems
- Dynomite & Exergy injectors
- Fuel rail & line upgrades
Exhaust & Intake Systems
Let your diesel breathe with a high-flow intake and exhaust system. We install S&B cold air intakes, aFe Power systems, Borla and Corsa exhaust, and custom downpipe configurations that improve airflow, reduce EGTs, and add that aggressive diesel sound.
- S&B & aFe Power cold air intakes
- Borla & Corsa performance exhaust
- Custom downpipe configurations
- DPF-back exhaust systems
- EGR delete kits
- Pyrometer & boost gauge installs
Transmission & Drivetrain
High horsepower demands a transmission that can handle it. We build and upgrade Allison, 68RFE, 6R140, and other diesel transmissions with Suncoast, Revmax, and BD Diesel components. From valve body upgrades to full billet builds, we keep your drivetrain together under serious power.
- Allison transmission builds
- 68RFE & 6R140 upgrades
- Suncoast & Revmax converters
- BD Diesel transmission kits
- Valve body upgrades
- Billet input shaft & clutch packs
Engine Builds & Internals
When you're chasing big power numbers, the stock internals have to go. We build diesel engines from the ground up using Carrillo connecting rods, Hamilton Cams, Manton Pushrods, Wagler Competition heads, and other top-tier components for engines that can handle whatever you throw at them.
- Carrillo connecting rods
- Hamilton Cams & Manton Pushrods
- Wagler Competition heads
- Industrial Injection components
- Head stud upgrades
- Full short block & long block builds
Performance Brands We Carry
39+ brands — hover to see brand names
Diesel Performance FAQ
How much power can I gain from a diesel tune?
A quality diesel tune on a stock truck typically adds 80–150 HP and 150–250 lb-ft of torque depending on the platform. With supporting modifications like a turbo upgrade, fuel system, and intake/exhaust, power gains of 300–500+ HP over stock are achievable on a Cummins, Duramax, or Power Stroke.
Will a tune void my factory warranty?
Technically, a tune can affect your powertrain warranty under the Magnuson-Moss Warranty Act if the manufacturer can prove the modification caused the failure. We can discuss your options and help you choose a tuning approach that minimizes warranty risk, including returnable-to-stock solutions.
What diesel platforms do you specialize in?
We work on all major diesel platforms — Cummins 5.9L and 6.7L (Ram), Duramax LBZ, LMM, LML, and L5P (GM), and Power Stroke 6.0L, 6.4L, and 6.7L (Ford). We also build competition engines for sled pulling and drag racing.
Do you do DPF and EGR deletes?
We offer emissions-related services for off-road and competition use only, in compliance with applicable regulations. Please contact us directly to discuss your specific situation and intended use.
How long does a diesel performance build take?
A simple tune and intake/exhaust install can be done in 1–2 days. A full compound turbo build or engine build can take 1–3 weeks depending on parts availability and scope of work. We'll give you a detailed timeline when you come in for a consultation.
Get In Touch
Get a Diesel Performance Quote
Tell us about your truck, your power goals, and your budget — we'll build a plan.