The 1971 Carter ThermoQuad: A Mopar OEM Carburetor That Is More Rare Than You Might Think

For a solid 15-year run from 1971 until 1984, the Carter ThermoQuad (TQ) was ubiquitous on Mopar four-barrel V-8 engines. Really an evolution of the long line of Carter four-barrels, the TQ was a break in tradition, moving from the square-bore configuration of the earlier AFB and AVS carbs to a spread bore layout similar to the Rochester Quadrajet. The original OEM ThermoQuad, debuting on the 1971 340, was a unique unit with different castings, metering circuits, and tuning parts. These 1971 carbs are quite rare, and pretty much orphans today outside the world of authentic restorations. Subsequent carbs were produced in huge numbers, and saw only minor changes through rest of the production run. Though the TQ was an all-new carb, the distinguishing characteristics of earlier Carter four barrels were still there. This was an era where fuel efficiency and emissions were major considerations, and the highly-refined ThermoQuad carb, with its small primary barrels, dual booster venturi, and three-stage metering rods was perhaps the most advanced four-barrel carburetor on the market… read more >