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Vintage Cars/Small block Chevy suffix code CLY identification


QUESTION: Hi, there's a few of us online who have been discussing a suffix code we can't identify. "CLY".  It doesn't appear on the GM suffix code list.  Here's a few things I know:  The engine code on the deck starts with V (flint) has 4 numbers for the day and month and ends with CLY. Mine is V0814CLY.   The block is painted orange but has had casting dates as late as 1980.  No partial VIN is stamped next to the code on the deck.  Here's my speculation:  I read that when no partial VIN is stamped next to the engine code that the engine was assembled off chassis.  I'm guessing if the engine was a replacement block at the assembly plant, like in St Louis (my car is a 1980 L82 Corvette) maybe they would grab a replacement block and build it to the spec of the model (like L48 or L82). I'm wondering if it's not listed in GM suffix code lists because of it possibly being a suffix that has a variable destination.  Any help would be greatly appreciated.

ANSWER: this is a well known issue , without a good answer, The best "specualtion" is that these blocks where originaly to be used in trucks of the era.  For some reason ( supply) they were used in some corvettes ( other cars ) as well.  Your theory would support this thought as well.  Truck data bases are much less complete than the car data bases when it comes to suffix codes.  Suffice to say you are not alone in this quest, to my knowledge it remains a mystry

Sorry I could not be of more help

---------- FOLLOW-UP ----------

QUESTION: Thank you for your reply.  I realize it's possible that it was meant for a truck - but just about as much as it's possible it was meant for a car.  On the one hand you make a point that truck data bases are much less complete.  And on the other hand if you check any GM suffix code listing you can see that suffix codes that begin with a C 99% of the time come out of a car.  And suffix codes that begin with a T 99% of the time come out of a truck, bus or van. ( And this one begins with a C.  So logic shows that it's as likely if not more likely that it was destined for a car.  I'm waiting to hear back from some people at GM and I'll get back with you if I find anything out so there's a record here.

that would be awesome, this topic has surfaced many time, surely there is a record somewhere at GM.  One other thought that I have ( not substanciated by facts)  is that these blocks were destined for something they planned on but did not produce ( car) . SInce it was a block common to many cars of the era , perhaps they got used up in what was going down the line  

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I can answer questions on W114/ W115 /W(R)107/W123/W126 Mercedes models 1967-1985. I have rebuilt many of these cars and have problem solved many issues. I have access to much of the technical data and have deailed instructions on fixing the most common issues. Vintage US 1950-1989 and other foreign cars as well If you are going to ask me about car value, please provide ample information on service history, rust issues, and current "needs". Pictures are helpful. Disclaimer on value - I can only give you data on what the market is bringing, and may not be what you want to hear!


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