Exhaust Headers Shorty for Dodge Chrysler Plymouth Small Block (1968-1980) 273-360 5.2L 5.6L

High-Flow Shorty Exhaust Headers for 1968-1980 Dodge, Chrysler, Plymouth (LA Small Block / A, B, E-Body)

What It Does: Replaces the restrictive, heat-retaining factory cast iron manifolds with mandrel-bent steel headers to optimize exhaust scavenging and significantly reduce backpressure.

The Stock Weakness

The factory "log" style manifolds found on the Mopar LA-series engines were engineered for low-cost mass production and tight engine bay packaging rather than volumetric efficiency. These heavy cast iron components create massive turbulence as exhaust pulses from adjacent cylinders collide within the common chamber. This restriction leads to significant heat soak in the cylinder heads and creates parasitic drag on the piston’s upstroke, robbing the engine of potential horsepower. Furthermore, decades of thermal cycling often result in hairline fractures and warped mating surfaces, leading to persistent exhaust leaks that can affect O2 readings and fuel trim in later models.

The Engineering Solution

These shorty headers utilize heavy-duty CNC-machined 7/16" head flanges to provide a warp-resistant, airtight seal against the cylinder head ports. Constructed with mandrel-bent tubing, the headers maintain a uniform internal diameter throughout every radius, preventing the bottlenecking found in stock units. This smooth flow path allows exhaust gases to maintain higher velocity, creating a vacuum effect that pulls spent gases out of the combustion chamber more efficiently—a process known as scavenging. The TIG and MIG welded construction ensures structural integrity under high Exhaust Gas Temperatures (EGTs). By streamlining the transition from the 1 3/4" x 1 1/2" inlets to the 2.25" collectors, this system delivers gains of up to 13HP and 11 lb-ft of torque.

Technical Specifications

Compatibility

• Dodge: Challenger, Charger, Coronet, Dart, Aspen, Diplomat, Magnum, Mirada, Dakota
• Plymouth: Barracuda, Cuda, Duster, Valiant, Volare, Satellite, Roadrunner, GTX, Fury, Belvedere
• Chrysler: Cordoba, LeBaron, New Yorker, Newport, Imperial, Fifth Avenue
• Engines: 273, 318 (5.2L), 340 (5.6L), 360 (5.9L) Small Block

The Mopar Muscle Standard

These headers are designed to deliver the iconic small-block Mopar rumble and increased throttle response demanded by classic muscle enthusiasts. Built for high-heat durability and maximum clearance, they provide the performance bridge between a stock cruiser and a street-strip machine.