Not long ago we were involved in a bench racing session with several veteran Vette aficionados that centered on the “good old days.” The cruise down memory lane centered on a particularly memorable trip decades earlier from California down through the Southwest in the middle of summer. As we regaled ourselves with our high-speed highway hijinks someone had the poor taste to remind us all of what it was like to change a fuel pump on the side of the road; rebuild an alternator in a Denny’s parking lot and worst of all, travel in triple-digit heat with the windows down, the vents open and no air conditioning. We were suddenly reminded that in some respects the good old days weren’t all that good.
When our early 1963 Corvette rolled down the assembly line, A/C was not offered, and when it did become available later in the year only 278 buyers chose the $421.80 option. But just because our coupe didn’t have A/C then doesn’t mean it can’t have it now, thanks to Vintage Air and its SureFit series. Available for 1958-’62, 1963-’67 and 1968-’76 Corvettes, Vintage Air’s Gen IV SureFit systems are designed to fit specific vehicles with little more that drilling some mounting holes.
In operation, the heater portion of any HVAC system passes hot water through a mini-radiator and a fan blows air through the core to provide warmth for the passengers. While that’s simple enough, cooling the air is a little more complicated, but essentially air conditioners make the air cold by removing heat.
The major components of an automotive air-conditioning system are: the compressor, evaporator (inside unit), condenser (outside heat exchanger), hoses, fittings, drier, safety switch and, of course, refrigerant. In operation, liquid droplets of refrigerant flowing through the evaporator absorb heat and turns to a vapor, the compressor draws the low pressure vapor from the evaporator and pumps it through the condenser where the heat that has been absorbed dissipates in the ambient air and as the refrigerant cools it becomes a high pressure liquid. From the condenser the refrigerant goes to the receiver/drier where the vapor and moisture are removed, it then passes through the expansion valve, which atomizes the refrigerant and turns it into a stream of cool, low-pressure droplets—and the cycle begins again.
Gen IV Technology
Vintage Air’s Gen IV units include a long list of features that were previously found only on modern OEM systems. A fully electronic servo operation eliminates vacuum motors or control cables for operation, increasing reliability and simplifying the installation process. In addition, servos provide increased butterfly door travel and more positive sealing for dramatic gains in airflow, superior defrost performance and true bi-level operation in both heat and A/C modes. Due to improved coil technology and CAD designed cases, Gen IV units deliver greater cooling/heating capacity and the servo controlled heater control valve provides true temperature blending in all modes of operation.
Vintage Air has gone to great lengths to simplify the installation of its SureFit kits, however there is some prep work that should be done before starting. Since an air conditioner removes heat from an enclosed area, the more heat you can keep from entering the passenger compartment in the first place, the more effective the A/C unit will be. Make sure the window and door seals are in good condition, and keep heat from the engine, exhaust and the sun from entering the passenger compartment by insulating the firewall, floor and roof. We’ve found Dynamat products to be extremely effective. Dynamat on the interior surfaces to stop vibration and reduce road noise, Dynaliner, DynaPad or DynaDeck to fight heat and low frequency hums from big engines and exhaust systems. Tinted windows will also reduce interior heat gain.
When it comes to putting the components in place, the Vintage Air system instructions are easy to understand and thorough. And on that subject, we cannot over emphasize the importance of reading those instructions from beginning to end before diving into the installation. In the case of the SureFit system we used in our 1963 Corvette, installing the evaporator requires several steps involving the new defroster duct and positioning and connecting the A/C and heater in a specific sequence. Not following the instructions may mean the evaporator installation will be a “do over,” and that’s not something you’ll want to do twice. While the entire kit is well thought out and beautifully executed, getting the evaporator into position is a challenge as it is an extremely tight fit. It took some jiggling and about the time we began to mumble to our self, it slipped into place.
With the evaporator in place the remainder of the installation is easy. All the A/C hoses have the ends installed (heater hoses are not included in the kit) the wiring harness is plug-and-play, new console side panels along with underdash A/C outlets are included and with minor modifications the original heater control knobs are retained (’63 center console trim will require some modification).
A Few A/C Tips
Rick Love from Vintage Air stresses the importance of the proper mounting of the condenser with respect to the radiator. While there should be enough separation to keep the condenser from touching the radiator core (approximately 1/8-inch), the condenser should be mounted more than 1/4-inch away from the radiator. It’s also important to consider some type of shroud, or seal, between them. Air will always take the path of least resistance and a shroud or “packing” (OEMs use foam or rubber seals) will ensure that cool air drawn by the fan will pass through the condenser and the radiator rather than pulling air around the condenser and into the radiator.
A critical but often-overlooked part of an air-conditioning system is a safety switch. These are extremely important since an A/C system relies on refrigerant to carry lubrication through the system. Vintage Air systems are equipped with a binary pressure safety switch (PN 11078-vus), which disengages the compressor clutch in case of an extreme low-pressure condition (refrigerant loss) or excessively high head pressure (406 psi) to prevent compressor damage or a ruptured hose. A trinary switch (PN 11076-vus) combines high/low pressure protection with an electric fan operation signal at 254 psi.
It’s critical that the heater control valve is installed in the heater hose running from the intake manifold (the pressure hose, closest to the thermostat) to the heater core. In addition, an arrow on the valve indicates the proper orientation in the hose (arrow points towards the evaporator/heater core).
Although the installation procedure is a do-it-yourself project, when it comes to charging the system that should be done by a shop with the proper training and equipment. Vintage Air systems are designed to operate with R134a only and should be evacuated for 35 to 45 minutes before charging with the proper amount of refrigerant. No oil should be added as the compressors come prefilled.
If the question is how to cruise your Corvette and keep your cool regardless of what surprises Mother Nature may have in store for you, one of Vintage Air’s SureFit systems is the answer. Follow Vintage Air’s instructions to the letter, prep the interior properly, have the system evacuated and charged correctly and you’ll have a state-of-the-art climate control system at your fingertips. Wouldn’t that be cool?
01. The Vintage Air SureFit A/C kit is clean and compact with everything necessary for installation, including compressor brackets and A/C hoses with the ends crimped on. The new Vintage Air A/C compressor mounts on the right side of the engine in place of the alternator. We will be mounting a one-wire, high-output alternator on the left side with the upcoming electrical updates.
02. Our 1963 Corvette coupe has been equipped with an AutoRad aluminum radiator and core support, which came with a condenser installed. Fortunately Vintage Air hard lines and receiver/driver bracket fit by spacing the condenser out slightly.
03. Vintage Air’s SureFit kit comes with a parallel flow condenser and the brackets to mount it to the factory core support/radiator assembly.
04. With the compressor mounted, the preformed #8 discharge hose was connected to the condenser’s inlet fitting.
05. For a proper seal, all the fittings are equipped with O-rings. They must be lubricated with the supplied oil during installation.
06. This is the Vintage Air drier and mounting bracket attached to the AutoRad condenser. Note the binary switch that has been installed in the drier.
07. Another safety switch option is the trinary, which can be identified by the pigtail with four wires (two for the compressor and two for engine cooling fan relay).
08. The Vintage Air hard lines tuck in around the right side hood hinge (not in place). Note the red and blue plastic caps, they are the service ports for charging the system.
09. In our coupe, the interior, instruments, glovebox, radio and the original heater had all been removed—it was a perfect time to install our Dynamat insulation.
10. This is the first Vintage Air component to be installed in the passenger compartment—the new defroster duct.
11. These plates cover the blower motor hole in the firewall (left) and the opening for the passenger side air vent (right), which is eliminated. The heater and A/C hoses are routed through the rubber grommets.
12. Here, the A/C and heater hoses have been routed through the cowl and into the passenger compartment.
13. When attaching the hose fittings to the evaporator, use two wrenches to prevent damage to the connections (we’ve seen them twisted like a cork screw from improper installation).
14. It’s a tight fit, but the evaporator assembly will fit between the crossbar and the firewall.
15. The #10 suction hose is connected after the evaporator is in place. Once tightened, the connection is wrapped with insulating tape.
16. We chose to retain the stock expansion tank; it hooks into the heater hose running from the heater core to the water pump.
17. Along with being oriented correctly, the heater control valve should be installed with the servomotor facing down.
18. The stock cable controls are removed, but the original knobs are reused.
19. Two of these switches will replace the stock cable controls; the third will be the temperature control in the new console side panel.
20. The screw-on 1963-’64 heater control knobs are drilled for D-clips to accommodate the new switches. Minor modifications to the stock bezels are also required.
21. This is the main wiring harness. It’s color-coded and includes a relay and circuit breaker. It is suggested that the ground wires connect directly to the battery and the red power wire connects to the starter solenoid or battery.
22. This is the wiring harness that plugs into new control switches (pots). The wires are color-coded—the plug with the red, white/blue, white wires isn’t used.
23. The main wiring harness and the harness from the controls plug into the control unit on top of the evaporator. The round device to the left is one of the servomotors that move the doors inside the housing.
24. As the new evaporator uses up space that was once occupied by the glovebox, Vintage Air includes a new (albeit smaller) replacement.
25. One of the holes to be drilled is for the evaporator drain hose—a small price to pay for A/C.
26. These are the underdash outlets. We’ll install those with the new interior and refurbished instrument panel that will be coming soon.
27. This is the new driver-side control panel. It includes the temperature control switch and a heat and A/C outlet. There is a replacement panel for the right side that also has a heat and A/C outlet.
28. To replace missing and damaged screws and hardware, we ordered a complete interior fastener kit from Totally Stainless. They can supply every fastener a Corvette requires from bumper to bumper.