Year	Engine	Horsepower	Torque (ft-lbs)	Carburetor	Comp. Ratio
1970	318	230@4400rpm	320@2000rpm	2 bbl	8.8:1
1970	340	275@5000rpm	340@3900rpm	4 bbl	10.5:1
1971	318	230@4400rpm	320@2000rpm	2 bbl	8.6:1
1971	340	275@5000rpm	320@2000rpm	4 bbl	10.3:1
1972	318	150@4000rpm	260@1600rpm	2 bbl	8.6:1
1972	340	240@4800rpm	290@3600rpm	4 bbl	8.5:1
1973	318	150@3600rpm	265@2000rpm	2 bbl	8.6:1
1973	340	240@4800rpm	295@3600rpm	4 bbl	8.5:1
1974	318	150@4000rpm	225@2200rpm	2 bbl	8.6:1
1974	360	245@4800rpm	320@3600rpm	4 bbl	8.4:1
1975	318	145@4000rpm	255@1600rpm	2 bbl	8.5:1
1975	360	230@4400rpm	300@3600rpm	4 bbl	8.4:1
1976	318	145@4000rpm	255@3600rpm	2 bbl	8.5:1
1976	360	230@4400rpm	300@3600rpm	4 bbl	8.4:1

Notes:

Torque specs vary depending on source. I've seen a lot of different torque numbers both in literature and internet web sites, so beware.
Data compiled from Chilton's Repair and Tune-Up Guide for the Valiant Duster, 1968-76.

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