Ribeye

I'm baaaack! My next project is to upgrade the existing air conditioning to a R 134a based system. I have been reading a lot on the subject and I would like to discuss this. I know I can upgrade the system by changing out the seals and putting in a new drier, but my compressor is shot and I need a new one. Is there an after market compressor that will fit the 1979 that has been designed for R134a?

Does anyone have any tips on doing this from lessons learned. No sense in me falling into the same traps as others..... Thanks to everyone for the help on the last issue, I really appreciate it...

mikep3

You can look at this link. They have a kit for 79 like the 76.http://www.classicautoair.com/GM_OEM_Parts_Compressor.html

http://www.ebay.com/itm/1977-81-CAMARO-Hi-Po-SMALL-BLOCK-A-C-Compressor-Upgrade-Kit-AC-Air-Conditioning-/400124369433?pt=Motors_Car_Truck_Parts_A ccessories&hash=item5d29455a19

7t9l82

i dont think i would consider 134a as an " upgrade ''

Ribeye

Thanks much....

Rotonda

Get a Sanden 508 compressor that is compatible with 134A. To mount, there are a number of options (vintage air and classic air), but many use Allan Grove mounts.

Use a parallel flow condenser (NOT stock, which is designed for R12) which will pull much less heat out of the 134a than the stock unit.

Your current system is an orifice system. You will have to change you orifice tube to a smaller (?) diameter to work effectively with the 134a.

You will need a new drier and will have to clean the oil from inside of the evaporator as lubricants for R12 and 134a are generally nor compatible. It would pay to disassemble the evaporator housing, clean the debris from it and the fan housing and replace all gaskets and O-rings.

After making new hoses (be sure to use a barrier hose designed for 134a - it has smaller molecules that will penetrate hoses designed for R12) you will be ready to go, with stock controls and an effective R134a system.

I did all of the above EXCEPT retain the stock evaporator/heater/fan. I replaced all with a Vintage Air system. I have done a write up on this project. If you wish to look at it, do a search under Rotonda.

If you have questions, please feel free to PM me.

Tom

DAVID SLUDER

Thanks for the great info I just ordered my compressor kit with hoses, condensor and brackets from classicautoair for my 79 vette, hope it works better than the stock system

chvet73

Search my old posts and you will find I did exactly what Rotonda did. Although I used a stock orifice. I get temperatures in the low 40 degree range. 134 works just fine if setup correctly.

jcloving

I've got a pro6ten compressor and I love it.

Parallel flow condenser
VIR eliminator
C4 blower with spacer
new seals

DAVID SLUDER

So you buy a C4 blower motor and where do you get the adapter? Is the air volume alot better?

SLVRSHRK

I did a similar thing a few years ago on my 78. The orifice tube you are looking for is the ford blue orifice tube. I just went to the parts counter at a local ford dealership and picked one up.

With 134a you need to have a finer screen in the orifice. The finer screen in the orifice will turn the liquid freon into smaller droplets than the original. More smaller droplets equals more surface area to absorb heat, which makes the system more efficient. It will work with the standard orifice tube, but it may not get as cool. That's the reason many folks complain that R134a is not as good in an old converted system.

Good luck.

jcloving

I bought mine from a place in Texas. Some guys make their own. It is 0.75" thick. Wood or plastic would work.

Yes, the air flow is significantly better. Almost enough to blow my hair back. The vane design moves more air. On MAX AC with the cowl door closed, you will notice more flow.

mac79vette

I am not at my home computer so I cannot post a photo but here is a link to my build and there is a few photos of the spacer that I made to adapted a c4 blower motor.
http://forums.corvetteforum.com/c3-g...-thread-4.html

mac79vette

I have been doing a little bit of research on upgrading compressors and was going to use Vintage Air for the compressor because I like the bracket when I used it on my 72 Truck and 56 BelAir. I spoke with Vintage Air and was told they do not have a bracket that will work if I am using a Corvette water pump because it is different in lengths that a Chevy short and long pumps. This was a while ago so they may have something now but its something to keep in mind.

IA_Stingray

To be clear, can you convert to R134a and still use the original compressor?

bille3821

Hi Tom, I'm wondering If I can get a copy of the write up you did on your air conditioning changes you did to your C3 Corvette I have a 1982 that needs an work on the air conditioning and thought I should upgrade at the same time. My home email is bill@wje.net.au thanks and regards Bill.