Factory Wheel Date Coding Issue

[J I.]

Dear NCRS Members, My 1972 LT-1 was built February 28, 1972. The wheels on the car are thought to be original. They appear with the following numbers K-1-5 followed by a space followed by "12" on the immediate left side of the valve stem and then on the right side of the valve stem the number "18" followed by "AZ". I've attached a photo, unsure if it uploaded. According to the judging guide the K-1- is supposed to be followed by a zero, one, or a two. Mine have a "5", yet "AZ" rims are 1970-72 rims. Makes no sense.

Can anyone help me decode my wheel numbers? If the date code is 1971, then the stamped "18th of December" makes perfect sense for a car built in Feb the next year. It's that danged "5" that has me puzzled!

Looking forward to some valuable insight. Thank you kindly!

[Jimmy P.]

Re: Factory Wheel Date Coding Issue

Hi J.
Its really tough to make out the number in your photo (to even be sure it's a 5). Is there another date code stamped inside the center lug nut area on your rim? My '73 had a stamp there too. It is actually clearer than the "3" up on the rim, by my valve core. Double check your rim to see!
Are all your other rims correct?
My second photo isn't that clear, hope the third close up is better!

[J I.]

Re: Factory Wheel Date Coding Issue

Hi Jimmy, Thanks for your response. All the rims have the same code...I did look for the center stamp on one wheel, but couldn't make it out. I'll look for the center stamp on the others right now. Back to you shortly!

[J I.]

Re: Factory Wheel Date Coding Issue

[Mark D.]

Re: Factory Wheel Date Coding Issue

December 18, 1975

[J I.]

Re: Factory Wheel Date Coding Issue

[J I.]

Re: Factory Wheel Date Coding Issue

Hi Mark....our judging guide book says only 70-72 rims were marked "AZ".

[J I.]

Re: Factory Wheel Date Coding Issue

The center mark numbers are too thickly painted to be made out with certainty. The 2nd posted photo clearly shows the K-1-5. I agree with Mark, they are likely 1975 rims. The confusing part is both the NCRS judging guide and the book "Corvette 1968-1982 Restoration" state that the "AZ" is for 70-72 wheels. Anyone else have anymore ideas? Thanks again Mark and Jimmy!

[Mike F.]

Re: Factory Wheel Date Coding Issue

Off the top of my head, I thought all 1969 thru 1982 15 x 8 Corvette Rally's were marked "AZ". I have a set of 1981's marked AZ. (K-1-81 5*29 AZ)

[Russ S.]

Re: Factory Wheel Date Coding Issue

You are correct Mike.

Off the top of my head, I thought all 1969 thru 1982 15 x 8 Corvette Rally's were marked "AZ". I have a set of 1981's marked AZ. (K-1-81 5*29 AZ)

[Russ S.]

Re: Factory Wheel Date Coding Issue

Without having the book I suspect it states 70-72 rims are stamped AZ but doesn't say only 70-72 wheels were stamped AZ

The center mark numbers are too thickly painted to be made out with certainty. The 2nd posted photo clearly shows the K-1-5. I agree with Mark, they are likely 1975 rims. The confusing part is both the NCRS judging guide and the book "Corvette 1968-1982 Restoration" state that the "AZ" is for 70-72 wheels. Anyone else have anymore ideas? Thanks again Mark and Jimmy!

[Terry M.]

Re: Factory Wheel Date Coding Issue

Hi Mark....our judging guide book says only 70-72 rims were marked "AZ".

I very much doubt the 1970-72 TIM&JG states that. I think Russ has it right. Just to help:
"Wheel Date Codes
Wheels are coded with the month, day, and size stamped near the valve stem. The size code for all 1970-1972 Corvette wheels is AZ. The month is stamped on one side of the stem while the day is stamped on the other side of the stem. The year is stamped in two places, one in the center hub and another near the valve stem...." The paragraph then continues to describe wheel dating and offers examples.

"The size code for all 1970-1972 Corvette wheels is AZ...." is not the same as "Only 1970-1972 Corvette wheels are AZ code." In fact 1969 to 1982 Corvette steel wheels are coded AZ.

[Keith K.]

Re: Factory Wheel Date Coding Issue

I have the 73-74 TIM&JG which says "The size code for all 1973-1974 Corvette Wheels is AZ". My understanding is that all 15X8 Corvette Rally Wheels 1969-1982 were AZ code.