Ah the 90+ degree days of Summer here in NC have started once again and I was just curious.... has anyone done anything to "supercharge" their AC?

I have an 81 and the AC works and while it will cool the car after 10 minutes on the highway on a really warm day, it is nothing like the AC in my 07 335i.

I realize mine is approaching 35 years old, but is there not any way to perhaps add a stronger motor to the blower? Bigger compressor? Better evaporator/condenser? Something?!??!

I'm not too familiar with the workings of an AC, but I thought there must be some way to make it blow colder air and more of it.

Thoughts?

 

my 2 cents based on recent experience.

1. check your a/c suction and discharge pressure to see that you have a sufficient freon charge

2. clean your a/c ducting and vents. It would be nice to remove and clean your evap suitcase box on the firewall, mine was full of leaves. I think you can remove the evap side cover and clean. Maybe not, I put my evap suitcase in as a unit as part of a complete a/c removal, clean and replace.

3. clean the condenser in front of the radiator.

4. check to see if the a/c control right thumbdrive bowden cable is stuck or partly open to make sure you are getting cold air off the evap and not outside hot vent air. Not sure how the vent flapper is set up on 77 through 82

5. put in at least one shutoff valve in the hoses to the heater core.

6. insulation under the carpet, reflextic from lowes (diy) or dynamat.

7. check for holes in the firewall for hot air entry into the cockpit

8. drive shaft tunnel insulation and foam collar on top of the bell housing (check vendor catalogs for photo or AIM) to reduce cockpit heat.

9. make sure your blower is blowing air

I got pretty good results doing all of the above plus removing and cleaning all lines and recharging with 134, got 56f out the center vent, which is ok with me.

Next step up is a swap out to a complete vintage air a/c system which folks say works great.
Hope this might help.

 

Your system is over 30 years old. Check it out as above.

If you have R-12, the original refrigerant, its likely to need hoses, O-rings, etc. as well as more refrigerant.

If your 81 has been converted to R134a, there are a number of possible improvements, such as a parallel flow replacement condenser, an improved Sanden 508 compressor, and a replacement (smaller) orifice tube.

Your system, regardless of refrigerant, could also benefit from a replacement fan. The popular choice is from a C4 which requires fabricating an approx. 1/2 inch spacer between the motor and the fan housing. Do a search - there has been much written. Yours is a common problem and the reason I put a Vintage Air system into my 77.

 

Did you modify the Vintage Air '76 for your '77? Would it be the same mods for a '79. I spoke to them at Vintage Air and they said they haven't worked on a '79 and could not help me.

 

I modified Vintage Air's kit for a 76 (ordered without any of the AC control changes). I have an early 77 with the VIR system. This is substantially the same as the 76 except for the controls and the center stack AC outlet. I detailed my changes in the following:
http://forums.corvetteforum.com/c3-t...in-a-77-a.html

My changes to the center stack and controls are applicable to your 79. The unknown areas are 1) Whether GM made any substantial changes to the firewall when they changed the body & interior in 78, and 2) Whether the unit would fit on the inside of your car, with the changes made to the RH dash to incorporate a glove box. Almost certainly you would lose the glove box.

 

Your car's A/C system....when new...worked better than almost any car ever made (then, or now). It had a system that could cool a Cadillac, but in a 2-seater vehicle. They blew LOTS of air and cooled quickly.

If your plenum is not clogged with 40 years-worth of tree/organic debris and is in good condition, there is no reason that it can't perform the same way.

You can replace what you now have, but it will cost more than fixing what you now have....and it won't work as well (as the original R-12 system). A new system may be more efficient, but not a better performer.

Take it to a GOOD auto A/C guy or gal and let them fix it up.