This is a Thermodyne Driver intake. This is a rare intake that is no longer being produced. It is for any pre-1986 style small block Chevy engine with a Holley or Carter/Edelbrock style carburetor.
It was an interesting design for sure. It is like brand new and has not been on an engine very long. It has a unique design in that it has passages underneath the carb base in each runner, which are attached to a venturi tube in each intake runner. I can only guess at the reason for this is to equalize the incoming fuel air mixture, maybe add some swirl to it too for more complete combustion and cylinder filling. Intake also has air gap technology as the carb flange is raised and there is a gap under it to cool the incoming mixture.
Also note the small ports. This was for low and mid range torque. Don't think this works for a high RPM engine.
Might be really good for towing applications, and I understand some used it for dirt track racing for more torque of the corners. I did not use this intake, so I cannot report how well it works. Sure is cool, and in perfect shape with no cracks, gouges or corroded spots. Looks and appears all but brand new but is used. Only ever seen two of these in a long career in parts. Think the company that made them was from the midwest and is long gone. The item "Rare Small Block Chevy Intake Thermodyne Driver Air Gap Holley or Edelbrock Carb" is in sale since Sunday, August 11, 2019. This item is in the category "eBay Motors\Parts & Accessories\Car & Truck Parts\Air Intake & Fuel Delivery\Intake Manifold". The seller is "datedcomponents" and is located in Hamburg, Pennsylvania.This item can be shipped to North, South, or Latin America, all countries in Europe, all countries in continental Asia, Australia.