Driving Innovation In Diesel Performance

Performance Cylinder Heads. Built for Cummins.

Choose your stage, pick your year range, and press Shop to land on the correct head. Our stages are designed to solve common Cummins head failures (dropped seats + soft plugs) while adding airflow where your build needs it.

Reman
1989 - 1998 12v HP Reman Cylinder Head

Performance Reman Heads

Fully reman’d Cummins head built to stop common failures HD seats, bronze guides, genuine Cummins valves, and thread-in plugs.

  • HD extra-large, heat-resistant valve seats
  • Thread-in soft plugs + genuine Cummins valves
Choose your year range
Shop Reman Head
Stage 1
1998 - 2002 ISB Stage 1 24v Cummins Performance Head

Stage 1 Performance Heads

HP Reman foundation plus 5-axis CNC porting and 105# springs more airflow and response while keeping the factory intake plenum.

  • 5-axis CNC porting with stock intake shelf
  • Intake flow up to ~220 CFM + 105# springs
Choose your year range
Shop Stage 1
Stage 2
VP44 Stage 2 24v Cummins Performance Head

Stage 2 Performance Heads

Stage 1 upgrades plus a replacement-style billet intake for even cylinder distribution more headroom without hot spots.

  • Billet intake retains MAP/air horn/TPS
  • Intake flow up to ~250 CFM + 115# springs/Ti retainers
Choose your year range
Shop Stage 2
Stage 3
6.7L Stage 3 24v Cummins Performance Head

Stage 3 Performance Heads

Max-effort 6.7 head for big power billet intake distribution, oversize super-alloy valves, and the airflow to support 1000+ hp builds.

  • Oversize super-alloy valves (1.500" / 1.450")
  • Intake flow up to ~300 CFM + billet intake distribution
Choose your year range
Shop Stage 3
Parts
D&J Cummins Head Gasket Kit 2003-2007 CR

Parts & Gasket Kits

Studs, gaskets, seals, and the supporting parts that make the install go right especially on higher boost builds.

  • Gasket kits, studs, seals, and install hardware
  • Everything to finish the job right the first time
Shop Head Parts
Knowledge Hub

Everything you need to know about D&J Cummins cylinder heads

D&J Cummins heads are built to fix two common failure points valve seats loosening/dropping and soft plugs pushing out while delivering stage-based airflow gains. Every head is fully cleaned, crack-checked, machined, CNC valve-job’d, surfaced, and assembled with new seals so it’s ready to install with confidence.

  • Stops common Cummins failuresHD extra-large, heat-resistant valve seats + thread-in soft plugs help prevent dropped seats and coolant-in-oil surprises.
  • Airflow matched to your buildChoose your head based on airflow needs: ~220 CFM (Stage 1), ~250 CFM (Stage 2), ~300 CFM (Stage 3).
  • Precision machine workCNC valve job, resurfacing, and careful assembly with new seals/soft plugs for repeatable installs.
  • Billet intake distribution (Stage 2/3)More even air distribution across cylinders helps reduce imbalance/hot spots while retaining key OEM sensors and mounting points.
  • Built to handle real diesel dutyDesigned around durability under load and heat cycles — from towing reliability to high-output combos.

FAQs

What problem do the upgraded valve seats solve?
Stock seats can loosen and drop. Our extra-large, heat-resistant seats transfer heat into the casting better and help prevent seat movement that can lead to failure.
Are these heads assembled and ready to install?
Yes — each head is cleaned, crack-checked, machined, surfaced, and assembled with new seals/soft plugs. Stage heads include the spring/retainer upgrades for that stage.
What’s the difference between Stage 1 and Stage 2?
Stage 1 adds CNC porting + 105# springs and keeps the factory intake plenum. Stage 2 includes Stage 1 upgrades and adds a billet intake for even distribution and additional airflow headroom.
Why does Stage 2/3 include a billet intake manifold?
It helps distribute air more evenly across cylinders to reduce imbalance/hot spots while retaining key OEM sensors and mounting points.
What supporting mods should match Stage 2 or Stage 3?
Airflow gains should match turbo, fueling, and tuning. Plan studs + quality gaskets when increasing boost and cylinder pressure.

*Fitment and outcomes vary by engine condition, supporting mods, tuning, and duty cycle.