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Oct 28, 2025 - 03:22 PM
The Sinister Diesel Blue Spring Kit with Adjustable Billet Spring Housing and Fuel Filter Cap for 2003-2007 6.0 Powerstroke increases fuel pressure by replacing the factory regulator spring with a stiffer blue spring, helping prevent injector starvation, improving injector longevity, performance, cold starts, and allowing fine-tuning for optimal results.
