Good afternoon,

I got my 1st vette about a month ago and i am starting to work on restoring it, At least to a daily driver. I live in Texas and summer is coming! The car had factory AC but seems to be mission the compressor (not sure if anything else is missing at this point) i would like to get my AC working again so i can drive it this summer, so i have been doing some research on the factory AC. The bad news is that the factory system doesn't seem keep up with the heat, but there seems to be so mods i can do to make the AC keep up, or just put in a newer system? I thought i would come see what others have done and see what is the easiest way to make it work.

 

Check out VintageAir or oldairproducts for repair and upgrade parts for the factory system or a complete new system that’s much better than oem.

 

1) Your 77 was, almost certainly, equipped with an R4 compressor. Replacements are available, but they weren't well regarded in the day and there are far superior compressors available (Please see Sanden 508).
2) 77's were a changeover year. Early 77's were equipped with a VIR (valve in receiver) system and later 77's were equipped with an orifice system. The VIR system was filled with problems and GM replaced it 4 years after it was introduced. The orifice system is still in use on current systems and can perform well in your 77.
3) If you are lacking a compressor, your system is almost certainly open to the air. This means that the system is filled with contaminated lubricant which will have to be cleaned out (disassembled) before anything else.
4) 77 systems were designed to work with R12 refrigerant. This has been discontinued but (possibly) available (though costly - though prices are somewhat down lately.) Modern systems use R134a refrigerant. R134a can be problematic in a VIR system, but will work in an orifice system ((Note - this usually requires changing the original orifice tube.) If converting to R134a, all of the hoses should be changed to barrier hose (original hose, intended for use with R12, is permeable to R134a and the refrigerant will gradually leak away). With such a conversion, you must also clean/change the system lubricant, and, for improved efficiency change the OEM condenser to a multipath condenser.

I have a 77 which had the VIR system installed. I installed a Vintage Air system because the effort and cost was about the same as renovating the original system. I'm not sorry I did. Vintage Air makes a very good system that will keep you cool (I live in S.W. Florida where you have 8 months of 90's plus heat with a LOT of humidity). If you need to ask questions, PM me and we'll go from there.

 

I too, have a factory AC system that is non-op. I plan to replace the entire system with the Vintage Air system on my '70.

BTW - they are in San Antonio.


https://www.vintageair.com/universit...958-thru-1976/

EDIT: just noticed you have a '77 and this is for '58-76.

Here:

https://www.vintageautoairconditioning.com/82corvette

 

You can have the best A/C system on the planet, but if you allow heat into the cabin its all for nothing.

When you slide your '77 temp control on the dash from hot to cold, you would think that would be the end of heat entering the cockpit. Not so. The control is at the mercy of vacuum action which as you likely know, is pretty iffy on a C3. You need to put a manual heater hose shut-off on either one of the hoses going to the heater core. NAPA sells two. A 5/8" and a 3/4". In the spring of the year you simply close the valve until it is needed again in the fall. You can hide the shut-off down near the original vacuum valve. Simply splice into either hose and clamp. You don't need a valve that looks like it belongs on your washing machine. Use automotive.

 

VA doesn't make a kit specifically for the 77. Others (and myself) have modded it to make it work and you can find the threads on the forum if you search. It is nice that it eliminates the vacuum hoses and protrusion into the engine compartment.