1973 Big Block 454 A/C Compressor - "HELP'"
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Cruising
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1973 Big Block 454 A/C Compressor - "HELP'"
I have a 1973 vette big block 454 with A/C --- I want to find the original compressor and date code for that year. The car is a 20 June 1973 build. I understand that for 1973 there were (2) kind of A/C Compressor's made. One was the "Superheat" type compressor with original GM part #2724178, however I think this one may have been discontinued and the other one is a "Metric" compressor with original GM part #12300276. Can anyone tell me for sure which one I need and how can you tell the difference between the two types. I know all of the A/C Compressor's were date coded and I know what date code to look for but I need to know which compressor I need. please HELP if you know for sure. You can email me direct with your answer at: bht@ak.net ---- Thank You, Tony
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From: Huntsville AL
THis is the first I have heard of two different types of compressors for 73. I believe that 73 was the year they changed from POA valve to VIR, but I'm not aware of different compressors.
I don't think there is a difference between 350 and 454 compressors, but I could be wrong.
I think I have an old 73 compressor from a May 73 build car. I'll check.
I don't think there is a difference between 350 and 454 compressors, but I could be wrong.
I think I have an old 73 compressor from a May 73 build car. I'll check.
Thread Starter
Cruising
Joined: Oct 2008
Posts: 11
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THis is the first I have heard of two different types of compressors for 73. I believe that 73 was the year they changed from POA valve to VIR, but I'm not aware of different compressors.
I don't think there is a difference between 350 and 454 compressors, but I could be wrong.
I think I have an old 73 compressor from a May 73 build car. I'll check.
I don't think there is a difference between 350 and 454 compressors, but I could be wrong.
I think I have an old 73 compressor from a May 73 build car. I'll check.
Thread Starter
Cruising
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Thanks Roger for the info - I guess there was only one type compressor made for 1973 --- I have no problem in finding the Green & Black Foil Label for the Big Block 454 #5910797 - I just need to find a compressor with the correct date code on the casing that I can use for my June built 1973 Vette. Thanks again, Tony
Team Owner
Joined: May 2005
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From: Huntsville AL
If you have one can you see what the date code numbers are on the casing and do you want to sell it - (how much) - if everything matches up for my use. It's the big long one with single belt pully. I guess I can have it reconditioned at a A/C Compressor shop. Thanks, Tony
It seems that at least one person thinks there are two different compressors for 73. One for the 350, and one for the 454. Mine is definitely for the 350, assuming I still have it. I haven't looked under that shelf in years.
I'll check and see what, if anything, I still have and let you know.
Team Owner
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From: Huntsville AL
OK, I checked, and I don't have the 73 compressor any more. I have a 75 Firebird compressor under the shelf.
I got the below info regarding the compressors from Joe Lucia over on the NCRS tech board. Good luck in your search.
The compressors are the same for both small block and big block. The difference is in the pulley/clutch assemblies. I believe that one uses a 5" pulley and the other a 5-1/2" or 6" pulley. I've forgotten which-is-which, though. There may also be some other difference in the pulley/clutch that I'm unaware of.
In PRODUCTION, the compressors are supplied complete with pulley/clutch assembly. Thus, there are different part numbers for the small block and big block units and different part numbers on the foil labels. In SERVICE, many compressors are sold without pulley/clutch assemblies, so one compressor services both engine applications.
I got the below info regarding the compressors from Joe Lucia over on the NCRS tech board. Good luck in your search.
The compressors are the same for both small block and big block. The difference is in the pulley/clutch assemblies. I believe that one uses a 5" pulley and the other a 5-1/2" or 6" pulley. I've forgotten which-is-which, though. There may also be some other difference in the pulley/clutch that I'm unaware of.
In PRODUCTION, the compressors are supplied complete with pulley/clutch assembly. Thus, there are different part numbers for the small block and big block units and different part numbers on the foil labels. In SERVICE, many compressors are sold without pulley/clutch assemblies, so one compressor services both engine applications.
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Thread Starter
Cruising
Joined: Oct 2008
Posts: 11
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OK, I checked, and I don't have the 73 compressor any more. I have a 75 Firebird compressor under the shelf.
I got the below info regarding the compressors from Joe Lucia over on the NCRS tech board. Good luck in your search.
The compressors are the same for both small block and big block. The difference is in the pulley/clutch assemblies. I believe that one uses a 5" pulley and the other a 5-1/2" or 6" pulley. I've forgotten which-is-which, though. There may also be some other difference in the pulley/clutch that I'm unaware of.
In PRODUCTION, the compressors are supplied complete with pulley/clutch assembly. Thus, there are different part numbers for the small block and big block units and different part numbers on the foil labels. In SERVICE, many compressors are sold without pulley/clutch assemblies, so one compressor services both engine applications.
I got the below info regarding the compressors from Joe Lucia over on the NCRS tech board. Good luck in your search.
The compressors are the same for both small block and big block. The difference is in the pulley/clutch assemblies. I believe that one uses a 5" pulley and the other a 5-1/2" or 6" pulley. I've forgotten which-is-which, though. There may also be some other difference in the pulley/clutch that I'm unaware of.
In PRODUCTION, the compressors are supplied complete with pulley/clutch assembly. Thus, there are different part numbers for the small block and big block units and different part numbers on the foil labels. In SERVICE, many compressors are sold without pulley/clutch assemblies, so one compressor services both engine applications.
Team Owner
Joined: May 2005
Posts: 31,497
Likes: 1,313
From: Huntsville AL
Thank you for the info and the time you took to look for the compressor. I sure do appreciate it. I have no problem in finding the correct green & black foil label for the 454 Big Block # 5910797 ---- I'll see what size pulley there is now on the car so I'll know what to look for. If you know of any places that have these reconditioned a/c compressor's please let me know - so far I have been stricking out - I did find one place in Arizonia that had (10) of these compressor's but they were all date coded from Mar 1970 to Nov 1972. I need one that is code dated anywhere from Feb 73 to the 1st week of June 73. I sure hope someone can help me out. I'm doing this for my son who was born in 1973. I want to leave him this nice '73 corvette before I kick the bucket. I never could afford one when I was growing up and I sure did want one so bad. Thanks again and Take Care, Tony
OK, just to make sure I understand, where is the date code on the compressor, and how do you interpret it?
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I'm not sure where the date code is excatlly but I understand it is stamped into the outer compressor casing somewhere for easing reading. This is how you interpret the date code: There are (6) numbers stamped into the casing: example - 021531 --- 02 means the month Feb --- 15 means the 15th day of the month ---- 3 means the year 1973 and the last number which can be 1,2 or 3 means the shift it was made on. I need a compressor that is stamp date coded anywhere from ----- 02xx3x to 06103x ---- That's anything from 1 Feb 1973 to June 10th 1973. Thank You Very Much, Tony
Thread Starter
Cruising
Joined: Oct 2008
Posts: 11
Likes: 0
I'm not sure where the date code is excatlly but I understand it is stamped into the outer compressor casing somewhere for easing reading. This is how you interpret the date code: There are (6) numbers stamped into the casing: example - 021531 --- 02 means the month Feb --- 15 means the 15th day of the month ---- 3 means the year 1973 and the last number which can be 1,2 or 3 means the shift it was made on. I need a compressor that is stamp date coded anywhere from ----- 02xx3x to 06103x ---- That's anything from 1 Feb 1973 to June 10th 1973. Thank You Very Much, Tony
Thank you .... Tony
