Product Description
S&S Diesel LLY-400SAC-R-SET 400% Over Injector Set (Reman) — 2004.5–2005 GM Duramax 6.6L LLY
Built for extreme power goals, the S&S Diesel Motorsport LLY-400SAC-R-SET delivers approximately 400% over stock flow using SAC nozzles, precise flow matching, and competition-grade build specs. Ideal for max-effort LLY builds with the right supporting fuel and air.
Fitment
- 2004.5–2005 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD
- Engine: 6.6L Duramax LLY (mid-2004.5 through 2005)
What’s Included
- Set of 8 remanufactured S&S LLY injectors with SAC nozzles (400% over)
- Flow-matched set for consistent cylinder-to-cylinder delivery
- Documentation / setup notes
Recommended Supporting Parts
- Duramax Injectors & Nozzles Category — browse related injector options for LLY.
- FASS Fuel Systems for Duramax — lift pumps & filtration to protect high-flow injectors.
- Exergy 12mm Stroker CP3 for 04.5–05 LLY — higher supply for big injector sets.
- Exergy 14mm Stroker CP3 Race Series for 04.5–05 LLY — competition fueling headroom.
- Fuel Injection Lines — Duramax — replace aged lines during injector service.
- 04.5–05 Duramax LLY Intercoolers — airflow support for high-power builds.
- S&S LLY TorqueMaster (Reman) — alternative lower-flow S&S option.
- S&S LLY 400% Over (NEW) — new-body version of this set.
Important Notes
- Competition product. Requires upgraded CP3(s), high-capacity lift pump, large-frame turbo(s), built transmission, and custom tuning.
- Verify local and federal emissions laws before purchase/use.
FAQ
Do these fit all 2004 trucks?
They fit mid-year 2004.5–2005 LLY applications only, not early 2004 LB7.
Are these truly 400% over stock?
Yes—this set uses SAC nozzles sized to approximately 400% over stock with S&S flow-matching and build specs.
What supporting mods are required?
At minimum: high-flow CP3 supply (stroker or dual CP3), quality lift pump/filtration, large single or compounds, built trans, and custom tuning.
Street-drivable?
These are intended for competition builds. For streetable power, consider lower-flow S&S options listed above.
Should I replace lines during install?
It’s strongly recommended to replace high-pressure lines and check return hoses; see our Duramax fuel injection lines.
