Marvel Model H Carburettor Air Valve Spring Type 1

As used in many Marvel carburettors including Buick 1922 through 1925

Free length O/All: 1.5" (38mm)

End Coil O/D: 0.4" (10mm)

Centre Coil O/D: 0.525" (13mm)

Wire Dia: 0.035" (0.8mm)

Centre closed coils length 0.31" (8mm)

To achieve 1/4” compression the pressure is 16 ounces (460gm)

to achieve 1/2” compression the pressure is 38 ounces (1090gm)