I bought a spare /6 from a guy and rebuilt it (my 1st rebuild). I just took the out my old /6 from my 1976 Dodge Dart. And upon closer inspection realized there is an extra hole between the egr valve and the thermostat housing on my rebuilt engine.... whereas on my 1976 Dart this hole does not exist.... any clues what I’m supposed to put in it? I posted some photos on Forabodies https://www.forabodiesonly.com/mopar/th ... 1972889283

They were used for emissions stuff. You can block them off. If you ever go EFI, they can be used for a GM CLR sensor.

Almost certainly a port for the CCEGR (Coolant Controlled Exhaust Gas Recirculation) vacuum switch. Sometimes these were in the head, sometimes in the top tank of the radiator, but they were a vacuum switch that would open or shut (depending on the application) based on coolant temperature.

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Casually looking for a Clifford hyperpak intake for cheap.

Yep, Reed and Kesteb have it. It is nice to have those extra coolant ports, in case you want to run an aftermarket temp gauge or sensor for EFI. Using an NPT plug for now will work nicely and won't hurt anything.

Lou

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Home of Slant6-powered fun machines since 1988

Thanks for the info! I’ll pick up a brass plug and block it off.