I don’t think I’ve ever seen one on a car, and a Mopar dealer on eBay I follow is selling them. I’ve got a 383, and live in crazy California, so would I need/want to have/add them? Are they necessary?
70 71 72 73 74 75 76 77 Mopar 383 400 440 Big Block Exhaust Manifold Heat Shield
Thx!
Referring to
70 71 72 73 74 75 76 77 Mopar 383 400 440 Big Block Exhaust Manifold Heat Shield, the item is a heat stove, not a heat shield.
The heat stove is for collecting exhaust manifold external heat and routing it to the air inlet on the air cleaner, in conjuction with a flexible duct hose, a vacuum driven door in the air cleaner and a thermal sensor (thermostat) to control the vacuum actuator on the air cleaner inlet door, or flap.
This is done to maintain a certain level warm temperature for emissions, driveability and cold weather warmup.
The system was introduced in 1970 on most non-fresh air applications. The following images are from the 1970 Serviceability Highlights describing the system.
The one shown in the eBay listing is for a standard exhaust manifold. The high performance manifold version is the same in function, but different in configuration due to the difference in the manifolds.
The high performance manifold that mounts the stove has a ridge and two screw hole bosses cast into it as shown in the following image:
This is a 2951865 casting number 1970 - 1971 manifold.
The manifold stoves will not work with headers without a lot of adaptation. To use the factory air cleaner heated air system with headers, hot air kits that clamp to a header tube such as the Hedman 24514 are available: