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I WILL BE A FIRST TIME OWNER OF A 1967 XR-7 THIS SPRING.
ONE OF THE FIRST THINGS I WOULD LIKE TO CHANGE ON MY
CAR IS THE TIRES AND WHEELS.
DOES ANYONE HAVE ANY THOUGHTS ON WHAT SIZE TIRES TO USE? WHAT I LIKE IS THE BF GOODRICH RADIAL TA SIZE
245/60 14.

THANKS,
JIM
 

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14's? If you're in the market for wheels you might as well go with at least 15's or 16's. The 15 inch wheel with 60 series tire is a nice combo - visually, as well as not too brutal on your finances.

The BF Goodrich tires have never done me wrong. I plan to put a set on my 2nd project shortly. I'm running Z rated Dunlop 50 series on my first cat and am very pleased with the tires performance - but they put a nice dent in the wallet.

Don't know if this helps any but it's my 2 cents either way ;)
 

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Jim, I'm sure the 245/60/14's will be fine on the rears but I think they will be too wide for the front. My brother has the 245's on back and 225's on the front of his 69 mach 1 on a set of magnums and we tried them on my 69 just to see how they look.

If your buying new wheels I would go along with putting 15's on but if your staying with present 14" wheels the above combo should be fine.mm
 

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Tire Size

Hi Jim,
I recently purchased a 67 and it came with 235/60/15s front and back. I plan to change at least the front tires to maybe some 205 or 215s because 235s are too wide and there is some slight fender rubbing during certain steering angles. The 235s are very similar in size to the F70-14s so you won't have to worry about speedometer errors ;) Anyway, if you go to this site, (one of many out there) it may help you decide on the size.

http://pw1.netcom.com/~sgalaba/tiresize.htm

Good luck!
 

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i have 215 75 ? 14 BFGs all around on te 69. the rears have a good chunk of room to spare, and the fronts are ok too. they do rub on the upper control arm at full lock though ( but that never really happens in the real world) i wanted fatter ones, but stock rims and the wallet wouldnt support much more at the time. i want a set of plain black steel 15s on the car next time, same hubcaps. but i cant afford a new set of tires for them at the moment. oh well.
 

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Tire size

Tire sizing is dependant on what rim width you will be using. Most tire manufacturers will give a recommended rim size for the tire size. They will say 6-7" or 7-8" or, in some extreme cases 6-8". If you try to put a tire that is too wide for the rim, the center of the tread will want to bulge out. To get the tire to sit or wear properly, you'll have to run a lower inflation pressure. Not a good thing. Tire wear will get all funny and handling gets weird.

The good thing about the current tire sizing is that you can easily match tire width. Actually, that's what that first number is, the 'section' width, or bulge width. This is a measure of the widest part of the tire on a standard recomended rim, measured in milimeters. Tread width is just that - the width of the normal contact patch.

The next number in the size is the aspect ratio. A 75 series tire is 75% as high as it is wide, a 60 series is only 60% as high as it is wide. Then we get to the really extreme ratios like 35s. These will look like rubber 'rim protectors' they're so short. Generally, the wider the aspect ratio, the better or more precise the handling of the car will be due to less sidewall flex. Ahhh, yes. The less flex in the sidewall also makes for a harsher, stiffer, less comfortable ride. Everything has tradeoffs. Sidewall stiffness can also be dependant on construction, but that is throwing other variables in here which may make things a bit confusing.

You will want to keep the overall tire diameter of your new tires somewhere near what was 'factory' on your car so the speedometer calibration stays close. Change tire size too much and you'll have to change the speedo gears, either in the tranny or at the end of the speedo cable. Yes, there are two gears. One is called the 'drive' gear that is on the transmission output shaft. The other is the 'driven' gear that is on the end of the speedo cable that goes into the transmission. By changing the number of teeth on either gear you will be changing the speedometer calibration. Since the average driven gear has about 18 teeth, changing this gear by one tooth will have about a 6% change in speedometer reading. Hmmm, but what if you're off by 3%? well, there are several ways to 'fix' the problem, but I won't go into that here.

OK, back to the tire size issue... If the recommended tire size for your car is an E-78-14, like most of our Cougars were, that translates to about a 205/75/14. Pretty wimpy looking, huh? To maintain the same diameter, you can go with a 215/70/14 or maybe even a 225/60/14. The F-75-14 works out to be 215/75/14 or 225/70/14. Most of our Classic Cougars came with 14x6" wheels. Anything wider than the 225 will probably need a 7" wheel width. Again, check with the tire manufacturer's rim width recommendations to be sure. The problem is, once you start deviating from the original, some things just don't look right. That's why they have the 'plus-1 and plus-2' idea. If you have a 225/70/14, you can step up to a 245/60/15 and maintain the same overall diameter. Anyway, your tire retailer can help you make the right choice here.

As for tire/body interference, that depends on several factors as well. Width, diameter and wheel offset. Those topics we'll discuss at a later time. Its late and I have to get to bed!
 

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You're bang on with the rim sizes Cougrrcj! My rear wheels are 15x7 and the 235s look fine but the front rims are 15x6 and the 235s seem to bulge out a bit...another reason for wanting to change them.
 

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Anyone have thoughts on some good wheels for a 70? I have the standard hubcaps,but would like some nice wheels. I was told to keep the car as much stock as possible, but am finding it difficult. I did see 1970 wheels at West Coast Classic Cougar, but I'm not too fond of them
 

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cost for the tires---- 300 ( 215/75/14 BFGs)
cost for the hubcaps ---- $15 from a local hubcap place
i like the look, i still have the original caps, but they look funny with the raised white letters. they are the like the ones on the car 6SCODE was showing. ( i think, ill have to check on that as soon as i finis typing this ) hey, its cheap and its the look im after. simplicity rules.
 

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Jebbster, are the 70 mach 1 gt style wheels correct for a 70 Cougar? If so my brother has a complete set he could be talked into parting with. There 14x7's or 8's, I cant remember off hand and the trim rings and center caps were mint the last time I saw them. There the plain centers, no gt emblems. There kinda rare. The holes are a little different shape than my 69's and there's not as many of them. They maybe what your looking for to keep a sharp but stock look. Anyone elses opinion on if these would be correct for a 70 Cougar? mm
 
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