Bob Johnstone's Studebaker and Avanti Page (Avanti Auxilliary Cooling Methods)

Avanti Auxilliary Cooling Methods and heat related items

Notes
High engine temperatures can be caused by many factors. Usually older Studebaker engines benefit greatly from having the block and radiator cleaned out. Drain plugs (3/8 pipe fitting) are located at the rear underside of the block above the starter and the oil filter. More aggressive cleaning can be accomplished if you remove the core plugs (freeze plugs) and brush the water jacket. If you have the heads off for valve work, this is an excellent time to get a wire brush inside the water jacket. You can trickle water into the topmost, forward point on the deck and let it run out the drain plug hole into a bucket. Spray some oil in the open cylinders if you're concerned about a problem with the water.
The standard Avanti radiator is only a 2 row.
Installation of a 3-row radiator has been reported to alleviate almost all overheating problems. A 4-row will not fit due to the angles of the fan and the radiator. This remedy should not be looked at before correcting all other mechanical deficiencies.

Excessive engine timing, either retarded or advanced, can affect the temperature. By retarding too much, you will lose power and force burning fuel past the exhaust valve. By advancing too much, you risk 'pinging' or detonation, which raises the internal cylinder temp very high and can burn holes in pistons. Some pinging can be tolerated but should not be allowed to continue to excess.

Incorrect spark plug heat range can cause overheating

Carburation can be a factor, in that too lean a mixture or low octane, can lead to detonation, raising temperature and causing major damage. A static , richened mixture is necessary on supercharged engines to offset detonation by cooling the intake charge, when in high blower (57-58 GH) or in a pressure condition (Avanti). The bigger jets are going to give you less gas mileage, but are necessary to cause the richer mixture when needed. There isn't any method of dynamically varying jet sizes.

Cleanliness can be a factor. If your engine is caked with dirt and grease, it can be inhibiting the natural radiation of heat by insulating the block.

Coolant hoses should be checked and replaced periodically to counter aged, swelling rubber compounds that may choke the water flow.

Engine coolant circulates through the heater core whether or not you are using the heater. As uncomfortable as it may get, you can turn on the heater in an emergency situation to add cooling capacity to the engine. On the other hand, heater hoses can be fitted with a shutoff valve in the engine compartment to prevent hot water from circulating through the heater core and radiating unwanted heat into the passenger compartment. This would significantly increase the comfort level in an air-conditioned vehicle, but fitting this valve, would counter the capability of the previous statement of using the heater as an emergency cooling aid.

Thermostats-
If your car overheats, don't remove the thermostat to remedy the situation. This can cause the water to pass through the radiator too quickly to get cooled and you'll still have the same or worse problem.
When you replace the thermostat, first put it in a pan of water with a candy thermometer and heat the water to a boil. The thermostat should open within 5-10 degrees of the spec. Don't take for granted they all work correctly, even if it is new.

There is a proven product called 'Water Wetter', which has been discussed on the chat group. Adding this to your coolant will drop the ambient temperature by up to 20 degrees.
The Avanti II ( up to at least 1976) have 1 1/8" cooling ducts which attach to covered intakes below the windshield grilles and run from the air intake, behind the dash and terminate on top of the transmission tunnel under the console, in front of the shifter. When the car is moving; cool, fresh air is forced into these tubes and is then played on the steel shifter mechanism. The bottom of the shifter is outside the weatherproof boot and is exposed to the latent engine heat passing under the car. It is also in close proximity to the exhaust. This heat is absorbed and convected upward to the handle and radiated into the interior. The handle can get pretty hot...
Early Studebaker Avantis didn't even have a grill at the base of the windshield. These were added as the first run progressed and things got improved on.. So you may not have the capability of tapping the fresh air intake there, but you can be innovative and get it from somewhere else. It is very effective.

The rubber gasket around the hood MUST seal the lid when it is closed, at least so, at the area right in front of the air intake grilles, at the base of the windshield. Failure to 'hermetically' seal the hood will allow superhot air to exit the engine compartment and be drawn right into the fresh air intakes and into the passenger compartment. Sealing this area will add effectively to keeping the occupants, somewhat more comfortable.
Some vehicles came factory equipped with holes cut in the engine compartment to add a source for cooling air / act as a vent to exhaust heat. Of course, this can allow road debris to enter the engine compartment.
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These photos are from Bob Lyles 1978

Then there's the Saturn Air Dam. This has proven itself to be the one best solution to any model/year Avanti. The application is not obtrusive and significantly increases air flow across the radiator while moving.
Installation pics
Instructions

Evans Coolant claims to be a super coolant that you don't mix water with and which has a very high boiling point .