HSU-4 1.5" SU carbs on a 76 Spitfire 1500 (US model)


I ran copper lines for the emissions and fuel supply.
I used sweat fittings on the 1/2" line, and compression fittings on the smaller lines.
The lines had to taper downward near the radiator to avoid hitting the bonnet.
Additional inline fuel filter installed before the carbs.
Below, where the lines enter and exit the carbs.

Rear carb above
Front carb below

Location of lines

  • 0 Emission line to cannister, tee's in with #6 & line from valve cover
  • 1 Mail fuel line IN from fuel pump
  • 2 Bowl vent, to cannister
  • 3 Fuel out to front carb (#4)
  • 4 Fuel IN for front carb 
  • 5 Bowl vent, to cannister (same as #2)
  • 6 Emission line to cannister, tee's in with #0 & line from valve cover