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OPEL-LESS!!!
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Discussion Starter · #1 ·
hey all, have a dumb question here but here we go. my dad had a GT in his day. i think somebody did alot of stuff to it but he claims it was all stock minus the weber. it had a 5 speed and such but i wanna know about his wheels. he says it had 10 inch wide "L-series" tires all the way around the car with a lower profile than what mine are, but not a low rider wheel. they used stock hub caps and looked like the wheels on my 70 GT. do these 10 inch wide L-Series wheels exhist? if so were they stock, option, or after market?
 

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Now THIS is a fun question! First, this designation refers to a tire, not a wheel. I remember when I was Jared's age, back when Camaros and "Stangs" ruled the earth, I had a friend that had a set of "L-60" series tires on the back of his '67 Camaro 327. Those were BIG FAT TIRES! Definitely aftermarket, and for the drag race set. His tires were almost "slicks", and as I recall, a few miles later they WERE slicks! Not much tread on those bad boys, especially with that SBC (with Holley 650 double pumper and "Three-Quarter" race cam, whatever THAT meant!) spinning them into smoke!

Now for the question at hand. A quick Google search (I just LOVE Google!) and a table popped up from the Tire Rack site (the table, for those that want the compleat story, is at:
http://www.tirerack.com/tires/tiretech/general/size_conversion.htm )

The Alpha-Numeric sizing was roughly equivalent to the older imperial numeric tire sizing, and designated the load carrying capability of a tire, and to some extent, the "Section" width, that being the widest part of the tire. The "L" series tire had a 9.15 to 9.50 inch section width, depending on diameter. The "Series" of a tire (the "aspect ratio", or the ratio of sidewall height to width) determined the diameter of the tire (or how "tall" it was). A standard tire back then was usually a "78" series, so the sidewall was 78% as tall as the section width. Ergo, an "L78-15" tire was pretty tall at 29.3 inches. Now a "60" series tire with otherwise the same designation was only 26 inches tall. I don't think that 50 series or smaller tires were readily available back then. Certainly not the 35 series tires that are on modern high performance sports cars today.

Anyway, I digress. It is possible that your dad did indeed have a set of "L" series tires that could have been nearly ten inches wide. I recall there being quite a few guys with Celicas and Corolla SR-5's that had "Grabber" 60 series tires. I don't know if they were "L" sized, but they could have been.
 

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OPEL-LESS!!!
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Discussion Starter · #3 ·
ok now i see that it is possable he had a L-Series wheel on his car, i'm going to see if i can find if the car came factory with them like he says, supposedly it used the stock chrome hub caps and beauty rings like a stock GT wheel. and your friends camaro, 327=GO GO!!! i like those, i have one thats going into my 51 packard, its not going to be done in time for my 16th birthday though so thats why the little opel came into the picture,lol.
 

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The factory stock tire, for all years of GT, was a 165R-13. The "Alpha" equivalent is an "A", or a 6.00-13 in the older American sizing standard. I believe they were "Eurometric" sized, which was was equivalent to an "82" series tire (82 % aspect ratio), so it was quite tall and fairly skinny. But at least they were metric, which was a new thing here in North America back then.

When I bought my first GT in 1977, it already had it's second set of tires, which were "165/SR-78" series, where the "S" was a speed rating (the lowest, as I recall). A major improvement came when I switched to 185/70-13's. The next size up that retains the stock diameter (for speedometer reasons) are 205/60-13, which is about 8 inches wide. But the stock wheel is only 5 inches wide, so you get a lot of sidewall bulge and tread rounding, unless the wheel is replaced with at least a 7 inch rim.
 

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OPEL-LESS!!!
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Discussion Starter · #5 ·
therefore i'm going to spend some change on a decent wheel and tire. oh well tires were new 500 miles before i got the car and still look decent and i have other things to worry about as of now, tires and wheels come later but i'm still going to look for that stock Lseries wheel.
 
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