I want to get a set of steel wheels and center caps for my car. I like the look of the COPO and ZL-1 "plain jane" cars. Does anyone know the correct backspacing for these wheels. They look like they are the same size all the way around.

Thanks,

Matt

The Std COPO wheels were 14 x 7 coded "XT" with a .4" offset. The optional Rally wheel was 14 x 7 coded "YJ" also with .4" offset. There was an option for a 5 spoke SS style wheel for a few months 14 x 7 with a "YA" code and a .4" offset and yet another additional option COPO-9737 for "sports car conversion" package that used the 15 x 7 wheels coded "YH" (same as the Z/28)that had a .3" offset. You probably want the "XT" coded style with the dog dish hubcaps. Hope this was not too much information.
-Mark.

Mark - I'm sure the refrence you make is 3" and 4" not 4/10th" (.4") I can't question the back spacing you give for the 14's. I do know that the YH 15's used on the later 69 z's had a 4" back spacing.

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...Dennis
"The '69 (http://chevelles.com/showroom/fine69_03.jpg), the '96 (http://chevelles.com/showroom/fine69_02.jpg) & the club (http://camaroslimited.com/)"

Mark,

That is exactly what I was looking for. Thanks for the help.

Matt

Dennis,
you are confusing backspacing with offset. Backspacing you are measuring from the inside rim edge to the mounting flange (not an engineering spec). Offset is either positive or negative and is a measure of how far the mounting flange is from the actual centerline of the rim, in this case 7" nominal. Since this is a very difficult measurement to do on an actual rim, we like to use the "Backspacing" method to describe wheels that are actualy in our hands when blueprints are not. If you want a comparison, take the offset (plus or minus) and add it to half of the rim width and you will be close to the Backspacing measurement. Using Z/28 Monte rims as an example...(7"/2)+(+.3)=3.8" now if you account for the fact that the rim is a bit wider at the flanges than the 7" nominal measurement, half that difference will show up in your actual measurements and you get closer to 4" "in hand" measured backspacing.

I get the data from an actual GM engineering bluprint and from Colvins "BY THE NUMBERS" book. Just a difference in semantics. The data posted should be right.

-Mark.

I understand offset vrs back spacing. The question refered to back spacing not offset. I did indeed overlook your usage of of the word offset in the post above though. Here's a diagram for offset.

http://www.tirerack.com/wheels/images/tech/offset.gif



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...Dennis
"The '69 (http://chevelles.com/showroom/fine69_03.jpg), the '96 (http://chevelles.com/showroom/fine69_02.jpg) & the club (http://camaroslimited.com/)"

I am new to the Camaro world (just purchased my first: a 1967 RS\SS 350 restored). I plan on keeping the original factory 14x7 rims along with the Firestone wide oval tires but would like to buy another set of rims (same style: Chevy ralley 15x8's all the way around) to enable me to put larger tires on it. I think I have found a combination that resembles the look I am looking for: P225 60R 15's on front and P275 60R 15's on back. My question would be is what do i need to look for in rim backspacing, etc. as you have discussed in your earlier postings. I am 36 yrs. old and have built a few chevy hot rods in my days from going to wrecking yard to wrecking yard rebuilding this part and that part.....can other chevy ralley rims fit my camaro as well (ie. early 70's monte carlos or novas or whatever)I like the idea of taking an old rim and sanding it down, repainting it, etc. rather than buying a brand new rim from some web site. Sorry for such a long posting; trying to learn about all this. I just sold my Vette (wife said we need more seats for the family to ride along with while i'm having fun)

Thank You

Brad