Thermoquad or Holley?

dartfreak75 said
One thing to add that I dont see anyone else mentioning that thermoquad is a later carb most of them after 75 were lean burn carbs and dont have the port for the vacuum advance for the distributor. I don't see the port in the pic you posted I'm pretty sure that's a lean burn carb!
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Actually, that's not quite correct. That port was never used for the distributor from the factory. It was used for the EGR valve. But you ARE correct in that it DOES make the perfect port for the distributor vacuum advance.