These IMCA Modified Long-Tube Headers are the best choice for your GM 604 crate motor.  They feature longer 1-5/8" to 1-3/4" stepped primaries for maximum torque and horsepower.

• 1-5/8"- 1-3/4" tube
• 3" collector
• Longer primaries for maximum torque and horsepower
• Bolts and gaskets included
• Best choice for a GM 604 crate motor
• Fits:
  • BMS
  • Dirtworks
  • Hoffman
  • Jet
  • KMOD
  • Bob Pierce
  • Sardeson
  • Smiley's
  • Victory