Rear Versus Front Tire Widths

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soonercruiser

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So, as I am narrowing down new wheels and tires for my 67 Barracuda, the thought occurs to me....
Although I am used to seeing all 4 tires the same width on passenger cars, that does not seem to be what I see on Classic cars.
In order to get my wheels and tires back into the wheel wells, I intend to go with narrower tires.
Currently, I have 255s on the rear; and 205s on the front.

So, the question it begs is.....
Can I go with 225s all the way around?
Why fatter tires on the rear?
Why so narrow on my fronts - 205?
 
Larger tires on the rear are generally for better traction if running a hot motor,if not then just for the "old school" cool look.

I have 275 on the rear and 215 on the front of my 72 Duster.
 
What wheels are you going with? I kind of like the look of a narrower tire in front. Not too narrow but a litte different size.
I plan on going with a 245/45 in front and a 255/45 in the rear for my Demon. Atleast until i figure out what wheels i'm going with. I am so indecesive, just want it to look good and be happy with my choice.
 
Ima thinking you don't have Factory Mopar wheels.

The Mopar wheels are all ZERO offset, AFAIK.
The factory steel wheels for a 67 Barracuda would be a
14 x 5, which measure 6 inches outside to outside, so would have a backspace of 3inches. From the Factory, it would have worn a D78-14 or a 6.95/78-14. That's a mighty skinny tire.
Every wheel has a particular size of tire, that will last the longest, at a factory specified tire pressure.
You can usually get away with one size either way.


Just so you know, on my 68 Barracuda ;
>on the back are 295/50-15s, on 10" aftermarket wheels, with a 4.5 backspace = a one inch offset.
>on the front are 235/60-14s on 7.5" aftermarket wheels, with a 3.75 backspace = a half inch offset.
>With these wheels, the treads are inside the tubs, but, the rearend was narrowed to make it happen.
 
4spdragtop said:
We have same car, so interested to learn.:popcorn:
Click to expand...
That's why I am asking.
On mine, I see no need to..1) have a fat *** ties sticking outside the body (I'm not dragging); and 2) The *** up in the air is too much.
I figure that I will be putting gas shock on the rear to adjust the height.
 
I believe a 225 will be too tall for the front.
 
OllieDemon45 said:
What wheels are you going with? I kind of like the look of a narrower tire in front. Not too narrow but a litte different size.
I plan on going with a 245/45 in front and a 255/45 in the rear for my Demon. Atleast until i figure out what wheels i'm going with. I am so indecesive, just want it to look good and be happy with my choice.
Click to expand...
With my goal to get the tires inside the wheel wells, my intention is to go with a 15x7 wheel.
That way all 4 wheels are the same, and can accomodate up to 9 in width tires.

My #1 choice on wheel is the AM Racing AR23 Series (cobo of good looks and good price).
#2 would be the US Mags U101 Indy wheels; albeit they are more expensive.
#3 the AM Racing Outlaw 2 wheels.

Since my motor is not "Hot" like some of you folks, I leaning towards 225s in the rear; 215s up front.; with Cooper GT tires.
 
NOW!
HERE IS ANOTHER CONCERN ABOUT THE WHEEL WELLS!!!

I'm currently on 15 inch tires with a 60 aspect ration.
All the tires I am seeing that I like are all 70 aspect ratio.
My head is swimming with drawings and numbers.....will the 15 inch /70 tires be taller????
(Over an inch taller by my calculation)
:rolleyes:
All this is in the context of finding wheels that will tuck back into the wheel wells. And I don't think the 1/2 inch ouside daimeter will be a problem for tucked-in tires.
And, there are far more 5x4.5 bolt pattern 15 inch wheel choices than 14 inch choices.
 
I always try to go with same height all around, even when I go with different sizes front and rear. I'm looking at 245 60 14 for the rear and 205 70 14 for the front of Vixen. They are very close to the same overall height. That way, I carry one spare, but still have the cool hot rod look.
 
soonercruiser said:
With my goal to get the tires inside the wheel wells, my intention is to go with a 15x7 wheel.
That way all 4 wheels are the same, and can accomodate up to 9 in width tires.
Click to expand...
Are you thinking of installing a tire with a 9" tread onto a 7" wheel?
Or one with a 9" profile?
Cuz, a 9" tread will have a profile about 1.5 inches wider, so say 10.5, which translates to about 267, which rounds up to a 275. But, a 275 on a 7" rim, at normal tire pressure, will pull the edges of the tread up off the road, and wear off the centers.
But
a 9" profile translates to a 225mm branded tire, which would be fine on a 7"rim.
Just remember, the rim width is determined by the measurement between the beads; and NOT from outside to outside which is always about ONE inch larger.

In other words, if you have a wheel that measures 7" from outside to outside, then it is actually a 6"wheel, and the ideal tire size for a 6" is about 218mm or less; so as already mentioned by others, rounds to 215.
To get a 215 up to 25.5 tall, on a 15, will require a branded tire of
215/65-15@26 tall or a
215/[email protected] tall

On our A-bodies, when the front tires get too far from stock height, you will get wandering issues.
A 215 gets lost in the rear tubs of a Barracuda/Duster/Demon/DartSport..
 
RustyRatRod said:
I always try to go with same height all around, even when I go with different sizes front and rear. I'm looking at 245 60 14 for the rear and 205 70 14 for the front of Vixen. They are very close to the same overall height. That way, I carry one spare, but still have the cool hot rod look.
Click to expand...
This is exactly what my '72 duster is wearing. I really like the look!
Google Photos
 
soonercruiser said:
So, as I am narrowing down new wheels and tires for my 67 Barracuda, the thought occurs to me....
Although I am used to seeing all 4 tires the same width on passenger cars, that does not seem to be what I see on Classic cars.
In order to get my wheels and tires back into the wheel wells, I intend to go with narrower tires.
Currently, I have 255s on the rear; and 205s on the front.

So, the question it begs is.....
Can I go with 225s all the way around?
Why fatter tires on the rear?
Why so narrow on my fronts - 205?
Click to expand...
What kind of car?
 
RustyRatRod said:
I got an error when trying to view, but I would like to see it.
Click to expand...
RustyRatRod said:
I got an error when trying to view, but I would like to see it.
Click to expand...

IMG_1849.jpeg
 
toolmanmike said:
:rofl: :rofl: Thanks, I'll blame it on my new glasses. Notchback or Fastback. Same rear wheel openings?
Click to expand...
They're the same on the early cars. I would assume the later ones too. But that's dangerous. lol
 
AJ/FormS said:
Are you thinking of installing a tire with a 9" tread onto a 7" wheel?
Or one with a 9" profile?
Cuz, a 9" tread will have a profile about 1.5 inches wider, so say 10.5, which translates to about 267, which rounds up to a 275. But, a 275 on a 7" rim, at normal tire pressure, will pull the edges of the tread up off the road, and wear off the centers.
But
a 9" profile translates to a 225mm branded tire, which would be fine on a 7"rim.
Just remember, the rim width is determined by the measurement between the beads; and NOT from outside to outside which is always about ONE inch larger.

In other words, if you have a wheel that measures 7" from outside to outside, then it is actually a 6"wheel, and the ideal tire size for a 6" is about 218mm or less; so as already mentioned by others, rounds to 215.
To get a 215 up to 25.5 tall, on a 15, will require a branded tire of
215/65-15@26 tall or a
215/[email protected] tall

On our A-bodies, when the front tires get too far from stock height, you will get wandering issues.
A 215 gets lost in the rear tubs of a Barracuda/Duster/Demon/DartSport..
Click to expand...
I've looked at several sites with charts describing wheel diameter versus what tire width will work.
A 7 inch wheel is supposedly OK for a 9 inch tire (profile). I would think that this would also give you a little sidewall protection from curb rashing your wheels. The tires I am looking at are 8.5 inches wide.
And, yes with what I have, I already have "wandering" issues.

At this very time in history, matching up 14 inch wheels and tires is much tougher.
 
Ok so just to get the terminology squared away;
Everybody I know, when talking about tires, never mentions the tread size. But, the profile width is an ethereal number, that is only accurate when the tire is installed on the checking wheel, on which it was installed, at the tire factory.

Now, when the tire company designs a 215 tire, it will only be a 215 on a checking wheel that is equal to 70% of the branded 215 size. Since a 215, converts to 215/25.4= 8.46 inches, and 70% of that is 5.925, which rounds to a 6" wheel.
Therefore, when you mount a 215, on a 6" wheel, it should have a profile width of 215 +/- 5mm.
Now then,
If you mount a 215 on a 7"wheel, the profile will be about half the wheel-difference larger . so then, your 215 become 215 plus half of one inch(an inch being 25.4mm), equals 227.5mm, +/- 5mm

I just thought that you should know this ... in case you didn't.
 
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