c4 to c3 A/C interchangability??
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
c4 to c3 A/C interchangability??
Hi all 
My vette - 1970 SB coupe, Auto. stock.
I had to have an A/C guy take the 'R12' parts of the air con off my vette before it got shipped to Australia (cause no R12 and no parts associated with R12 are allowed to come into the country......stupid laws!)
Im not sure exactly what parts were taken off.......but whatever was R12 I guess. (drier?, some seals and hoses?).
Ok so heres my question.
I was wondering if the A/C components that were removed can be replaced with the components off a c4 (1989) vette?
Reason why Im asking, the c4 air con parts are going cheap....(parts for vettes are generally hard to come by here in Australia).
Looking forward to hearing your thoughts.
My vette - 1970 SB coupe, Auto. stock.
I had to have an A/C guy take the 'R12' parts of the air con off my vette before it got shipped to Australia (cause no R12 and no parts associated with R12 are allowed to come into the country......stupid laws!)
Im not sure exactly what parts were taken off.......but whatever was R12 I guess. (drier?, some seals and hoses?).
Ok so heres my question.
I was wondering if the A/C components that were removed can be replaced with the components off a c4 (1989) vette?
Reason why Im asking, the c4 air con parts are going cheap....(parts for vettes are generally hard to come by here in Australia).
Looking forward to hearing your thoughts.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
While some on the forum are using R-134a in the A6 compressor, the A6 is large & heavy- not what one wants in the design requirements for a high perf. sports car.
A/C Compressors
It's easy to change compressors, basically brackets & hoses are needed. Size about 8 C.I. to about 10 C.I. (rotary).
The 89 used a rotary compressor (as did a 77). The rotarys are small, light & out of the way. New ones last about 10 years- used & rebuilt are not rec.
It is possible to put in a small light compressor that uses less HP like a ND or Sanden 508 (8.4 C.I.). Aftermarket brackets are available.
This shows a ND 6P w/ my brackets. About 8.2 C.I. & works great. Note how the A/C lines go off to the side & then straight forward & back.
http://ganeys.home.sprynet.com/77ACs.JPG
A/C Compressors
It's easy to change compressors, basically brackets & hoses are needed. Size about 8 C.I. to about 10 C.I. (rotary).
The 89 used a rotary compressor (as did a 77). The rotarys are small, light & out of the way. New ones last about 10 years- used & rebuilt are not rec.
It is possible to put in a small light compressor that uses less HP like a ND or Sanden 508 (8.4 C.I.). Aftermarket brackets are available.
This shows a ND 6P w/ my brackets. About 8.2 C.I. & works great. Note how the A/C lines go off to the side & then straight forward & back.
http://ganeys.home.sprynet.com/77ACs.JPG
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Le Mans Master
Joined: Mar 2002
Posts: 7,456
Likes: 2
From: Coming home from Luckenbach Texas
You could use the R4 compressor off an '89 and convert it to R134 use. However, I think you'd need the brackets off a late C3 (78-82).
Quite frankly, however, if you could score a set of compatible brackets for the R4 compressor, I don't see why you couldn't use bits from the Holden parts bin. I'll bet Holden even used the R4 compressor during the '80s.
BTW: That's not just stupid law, it's a really stupid law. Does it matter if the R12 freon leaks into the atmosphere in the USA or Down Under. I think not!
Quite frankly, however, if you could score a set of compatible brackets for the R4 compressor, I don't see why you couldn't use bits from the Holden parts bin. I'll bet Holden even used the R4 compressor during the '80s.
BTW: That's not just stupid law, it's a really stupid law. Does it matter if the R12 freon leaks into the atmosphere in the USA or Down Under. I think not!
Le Mans Master
Joined: Mar 2002
Posts: 7,456
Likes: 2
From: Coming home from Luckenbach Texas
Here's another thought. Check out the Vintage Air website (www.vintageair.com). You can get a Sanden R134 compressor and custom brackets for very reasonable prices, and I imagine they ship internationally. They may even be able to put together all the stuff you need.
If not, you can have hoses fabricated locally...and once again I bet a few Holden bits will finish the job. Any reputable A/C shop should be able to tackle this one with a minimal amount of fuss.
If not, you can have hoses fabricated locally...and once again I bet a few Holden bits will finish the job. Any reputable A/C shop should be able to tackle this one with a minimal amount of fuss.
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
Thanks for the replys guys and gals. Definitly a biiiig help, I really appreciate it. Given me some things to think about.
The holden thing is a good idea to look into. I just thought while these c4 parts were going cheap I may be able too use them.
I thought it would be a good idea to have some parts available and have a clue of what was involved so the a/c place can't pull one over me or something!
The holden thing is a good idea to look into. I just thought while these c4 parts were going cheap I may be able too use them.
I thought it would be a good idea to have some parts available and have a clue of what was involved so the a/c place can't pull one over me or something!
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Hey Ganey-
How many different spots does your compress mount in?
How does it perform relative to the stock unit?
My stock compressor is off on the 78 and I would really prefer to replace it with something with less drag and more A/C performance.
Which do you recommend, the Sanden 508 or the ND?
Still uses stock belt I imagine.
-Steve
How many different spots does your compress mount in?
How does it perform relative to the stock unit?
My stock compressor is off on the 78 and I would really prefer to replace it with something with less drag and more A/C performance.
Which do you recommend, the Sanden 508 or the ND?
Still uses stock belt I imagine.
-Steve
Burning Brakes
Joined: Jun 2005
Posts: 764
Likes: 2
From: THE OLDER I GET THE BETTER I WAS! NORTHERN ONTARIO
I have a 79 used all new parts that fit the 79 model year rotary compressor hoses dryer condenser evap & all... charged it 134a no prpblem...I don't understan your law if it looks old it can't be good? why can't you use tha parts that work with your car & charge with whatever refridgerant "they" want you to use?
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
I have an 89 serpentine belt setup on mine with the 89 "sanden style" compressor (made by Nippendenso). I had to make a custom hose for it, but it's not too complicated-the stock hose would be too short for a long type compressor. The manifold blocks are the same. I am using R12, but the same compressor with different top plate (interchangable) was used on the LT1s that used R134. Hope that helps.
Racer
Joined: Mar 2004
Posts: 292
Likes: 2
From: Plumas Lake CA
Anyone ever mount a C4 evaporator box/blower motor and heater core in a C3? I've heard of converting the blower to a C4, but I would think the rest of the parts might make the conversion to serpentine belts and more efficient compressors a little bit easier (bolt on). I've basically been pondering the idea of a complete swap to C4 heater and airconditioning.