Question: Chrome bumper C3s: 1970 / 1972 differences?

[hand_coder]

All:

I'm working on a Spotters Guide feature for my "Corvette Story" web site. Currently I'm working on the chrome bumper C3s and I have it mostly figured out EXCEPT how to visually determine the difference between a 1970 and 1972 'vette. Both have the eggcrate grill on the front and the front fenders. Both use a clear front turn signal lens with a amber bulb. And the 1971 uses a amber front turn signal lens. Or so that's my understanding. Is there a visual clue that can distinguish the difference between a '70 and '72? About the best I can do is to point out that the '72 did away with the fiber optic interior indicator system, but I was hoping there was some way to determine the year externally.

Thanks in advance!

 

[3dale1]

The eggcrate grilles on the fenders will have only horizontally chromed lines on them. 71-72 will be both vertical and horizontal.

68-71 used green lettered gauges, and in 72 they were changed to white.

Pretty sure that cars 68-71 used a slightly different style/pattern of heater control face controls than 72 and up cars.

I thought that 70-71 used CLEAR front lenses, and 72 was amber?

 

[Crimson Thunder]

1970 front grills does not have exposed phillips head screws to hold them on.

 

[hand_coder]

The eggcrate grilles on the fenders will have only horizontally chromed lines on them. 71-72 will be both vertical and horizontal.

That's interesting about the chromed lines lacking on the '70. The photos I have are inconclusive and the factory images don't show that area well for the '70..

I thought that 70-71 used CLEAR front lenses, and 72 was amber?

Quoting the Corvette Black Book, 1971: "Production specifications called for amber parking light lenses, but most 1971s had clear lenses with amber bulbs as in 1970" So this is why I see some 71s with amber parking light lenses. The book doesn't say anything about the '72s.

My basis for saying the '72s had clear lenses is this factory photo:

.

This is from GMs media.gm.com site, note the "1972" license plate. But they have been known to be wrong on more than one occasion and in looking at my photos I see a couple of '72s with amber lenses, so you could be right.

It's all kind of difficult to say for sure, so I'll have to put all kinds of caveats in the article. Thanks for the reply.

 

[hand_coder]

1970 front grills does not have exposed phillips head screws to hold them on.

I think they have one screw in the top - see photo below.

"Click Here" to see a larger image.

Here is a photo of a 1971:

(larger image)
There are three phillips head screws which is the difference, at least that's what my photos indicate.

I'll add the info to the article but its of limited usefulness since you have to be up close and you can't discern the differences while the car is being driven. But it looks like it'll have to do.

Isn't being a Corvette detective fun?

 

[6880 Mike]

Order the 70-72 NCRS Judging Guide. It lists the differences in the 70-72 model years. Visually, the three years are very, very similar.

 

[hand_coder]

Order the 70-72 NCRS Judging Guide. It lists the differences in the 70-72 model years. Visually, the three years are very, very similar.

An excellent idea! (Why didn't I think of it?)

 

[6880 Mike]

...(Why didn't I think of it?)...

Ya got me on that one.