Part # question for a '73 AIM
Thread Starter
Pro
Joined: Jul 2004
Posts: 711
Likes: 61
From: Waterford CT
Part # question for a '73 AIM
Does anyone out ther have a Assembly Instruction Manual for a 1973 that can check a part number for me. I need to know is Part #3956118, lower fan shroud extension is the right part for a small block car? I recently bought a '73 convertible and found that the lower extension is missing. There's one posted here on the forum advertised as for '70 to '72 and I'd like confirmation that it will also fit my '73 before I pursue it.
Thanks for the help!
Thanks for the help!
Burning Brakes
Joined: Sep 2005
Posts: 1,050
Likes: 205
From: Lewes Delaware
The lower shroud extension was for a 454 engine. The small blocks had a complete "circle" extension. Check this out from Paragon:
Small blocks:
https://www.paragoncorvette.com/p-35...extension.aspx
Big block 454
https://www.paragoncorvette.com/p-35...extension.aspx
Small blocks:
https://www.paragoncorvette.com/p-35...extension.aspx
Big block 454
https://www.paragoncorvette.com/p-35...extension.aspx
Thread Starter
Pro
Joined: Jul 2004
Posts: 711
Likes: 61
From: Waterford CT
thanks
Thanks for the help guys. Although mine is a small block car with a '74 dealer replacement engine, I do have the composite shroud. It appears to be very much like the shroud in my '71 LT-1, but I can't compare at the moment as the '71 is a couple miles away in a borrowed garage! I will have to keep looking and I guess I should find out what the GM part number is for the big block shroud which is what I may have.
Race Director
Joined: Oct 2000
Posts: 12,658
Likes: 3,117
From: Shamong, NJ
The small block shroud extension is part #331870, and is used for all 73-75 350's. The 73-74 big block extension is part #336152.
Drifting
Joined: Jul 2005
Posts: 1,562
Likes: 2
From: Spring Texas
I don't have the 73 AIM, and GM is known to change part numbers. I have a PDF copy of the 53 - 82 parts manual, and it confirms the 73-75 shroud part # of 339175. I get different part numbers for the lower extensions. #327695 for the small block, and #336176 for the big block.
I know that just muddies the water.
I know that just muddies the water.
Race Director
Joined: Oct 2000
Posts: 12,658
Likes: 3,117
From: Shamong, NJ
I don't have the 73 AIM, and GM is known to change part numbers. I have a PDF copy of the 53 - 82 parts manual, and it confirms the 73-75 shroud part # of 339175. I get different part numbers for the lower extensions. #327695 for the small block, and #336176 for the big block.
I know that just muddies the water.
I know that just muddies the water.
I have about a dozen original (printed paper) Corvette Parts Books, dated between 1970 and 1983, as well as a microfiche edition. Though I didn't check all of my Parts Books, both my Sept. 75 and Sept. 83 dated editions, show the same part numbers, as I previously posted.
I don't have an open 73 AIM, but my 74 AIM also lists the same part numbers for the extensions (331870 small block and 336152 big block).
I also have 2 NOS big block extensions on my self, and both have 336152 molded into them.
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Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
Mike:
I have 73 AIM. Sheet 13-E -1 Lists Shroud as 3956108. Extension for L48/LT1 as 3956118. Sheet 13-E-2 Lists extension 3974014 as the one for the LS4. My 73 has L82 and has the correct extension on it. It currently is in one of my other garages so I can't send you photo tonight.
Unk
I have 73 AIM. Sheet 13-E -1 Lists Shroud as 3956108. Extension for L48/LT1 as 3956118. Sheet 13-E-2 Lists extension 3974014 as the one for the LS4. My 73 has L82 and has the correct extension on it. It currently is in one of my other garages so I can't send you photo tonight.
Unk
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Race Director
Joined: Oct 2000
Posts: 12,658
Likes: 3,117
From: Shamong, NJ
Of course, 73 didn't have an LT-1, as an option, so it's could be an early sheet, that was later revised?
Sheet 13-E-2 Lists extension 3974014 as the one for the LS4
Unk
Unk
Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
It is hard to argue with an AIM that has numbers that match an actual 73 car! The original posting was asking if the number was correct for a 73 per the 73 AIM. The same AIM drawing I referenced is shown in the NCRS 73 judging guide on page 81 Figure M 5.0. The drawing showing extension number 331870 is shown on Page 82 Figure M5.1 and is stamped "Cancelled".
The confusion seems to be the result of people trying to use other documents than the one requested in an attempt to provide an answer.
Since it was questioned, the date on the 73 AIM manual drawing listing the part numbers shows the drawing was made on March 17, 1972 as the result of an Engineering Change Request number 43746 that was dated February 15, 1972.
The fact that an earlier or later Parts Listing for multiple years shows something else just shows why those lists may not show it all. I have had dealer parts people tell me something didn't come up on their list, but when we dig into their old records we find the number was correct.
If you want a real exercise in multiple numbers for a given year, check out the fan shroud situation for a 76, they made a change mid year.
Unk
The confusion seems to be the result of people trying to use other documents than the one requested in an attempt to provide an answer.
Since it was questioned, the date on the 73 AIM manual drawing listing the part numbers shows the drawing was made on March 17, 1972 as the result of an Engineering Change Request number 43746 that was dated February 15, 1972.
The fact that an earlier or later Parts Listing for multiple years shows something else just shows why those lists may not show it all. I have had dealer parts people tell me something didn't come up on their list, but when we dig into their old records we find the number was correct.
If you want a real exercise in multiple numbers for a given year, check out the fan shroud situation for a 76, they made a change mid year.
Unk
