tire clearance issues

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moparfanatic56

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ok guys, I need some direction on rear tire to fender clearance on my 72 dart other than different rims with a deeper offset (not in the budget). I have 235/60/15 tires mounted on cragar ss 15x8 with 3.5 in offset, I just put air shocks on as regular shocks didn't work and even with 110-120 lbs of air pressure the fender is still on the tire. What are my options shock extensions or are there any other options if shock extensions are they still available? Thanks
 
Wait until you have the budget to do it correctly with 15x7" rims. 15x8" is a reverse offset rim.
Everything you are trying to do is just a bad band-aide.
If you did finally get the rear up high enough your car will ride like a stiff truck as you will have no give in the suspension.
And if the air shocks fail at speed it could be a disaster when the tires land on the fenders and get cut and/or go flat.
 
Yup, pumping up the Air Shocks is just gonna break the shock crossmember... It was never designed to support the car, only dampen the movement on the suspension...

You have the wrong rims... Period, end of discussion... Sorry..
 
MoparLeo said:
Wait until you have the budget to do it correctly with 15x7" rims. 15x8" is a reverse offset rim.
Everything you are trying to do is just a bad band-aide.
If you did finally get the rear up high enough your car will ride like a stiff truck as you will have no give in the suspension.
And if the air shocks fail at speed it could be a disaster when the tires land on the fenders and get cut and/or go flat.
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Please bear with me I have been out of the car scene for about 40 years and things are alot different. I want make sure that I am understanding this correctly. The 15x7 rims will give me the offset I need with the tires that I have.
 
1WildRT said:
Yup, pumping up the Air Shocks is just gonna break the shock crossmember... It was never designed to support the car, only dampen the movement on the suspension...

You have the wrong rims... Period, end of discussion... Sorry..
Click to expand...
No apology needed, I was pretty sure that was going to be the answer I was going to get. Thanks, guess I will be looking for new rims lol.
 
moparfanatic56 said:
Please bear with me I have been out of the car scene for about 40 years and things are alot different. I want make sure that I am understanding this correctly. The 15x7 rims will give me the offset I need with the tires that I have.
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You need wheels with a larger backspace. They sell 15x7’s in the wrong backspace too, so just going to 15x7’s may not fix your issue.

Other than having a ‘72 Dart, how is it set up? What rear axle is in there? Is it the small 5x4” bolt pattern or has it been upgraded to 5x4.5”? That will make a difference with what you need for wheel backspace. You can run 15x7’s or even 15x8’s and re-use your current tires, but the backspace will have to be right either way.
 
I was assuming you still wanted to run the Cragar S/S rim.
The 8" rims used for decades on aftermarket type wheels have mainly been reverse offset, also called deep offset rims.
15 x 7" are normally steel rims, 7 1/2" usually alloy.
There are exceptions on anything of course and as 72bluNblu says, more details of your drieline would help to give you more info.
It is always best of course to do your own research as well.
Easy to go to the different wheel companies websites to look up fitment info.

Series 08/61 Cragar S/S - The Original Muscle Car Wheel

Series 08/61 Cragar S/S known as The Original Muscle Car Wheel, the S/S line is our most popular custom wheel designed by Roy Richter.
www.cragarwheel.com www.cragarwheel.com
 
72bluNblu said:
You need wheels with a larger backspace. They sell 15x7’s in the wrong backspace too, so just going to 15x7’s may not fix your issue.

Other than having a ‘72 Dart, how is it set up? What rear axle is in there? Is it the small 5x4” bolt pattern or has it been upgraded to 5x4.5”? That will make a difference with what you need for wheel backspace. You can run 15x7’s or even 15x8’s and re-use your current tires, but the backspace will have to be right either way.
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It is a 8.75 that has been upgraded to the 4.5 in bolt pattern.
 
  1. You have a baseline with what you have.
  2. Measure how far out the tires are to the wheel opening.
  3. Measure how much space you have between the inside of the tire and the spring
  4. Measure mow much space you have between the tire and the inner fender well.
With these numbers you can determine what back spacing you need verses the back spacing you have now.

Example.
These are only numbers for the example
Tire sticks out 1 inch
There is 2 inches from inside of tire to inner fender well
There is 1.75" inside of tire to spring

Your current back spacing is 3"

You need to move the wheel /tire combo inboard by 1.25 inches to clear the fender lip.

You have 1.75" on the inside.

So when you get your new wheels with 4.25 back spacing (existing 3 plus the 1.25 you need to move the tire) you will have 1/4" on the outside and 1/2" on the inside clearance.
 
Dana67Dart said:
  1. You have a baseline with what you have.
  2. Measure how far out the tires are to the wheel opening.
  3. Measure how much space you have between the inside of the tire and the spring
  4. Measure mow much space you have between the tire and the inner fender well.
With these numbers you can determine what back spacing you need verses the back spacing you have now.

Example.
These are only numbers for the example
Tire sticks out 1 inch
There is 2 inches from inside of tire to inner fender well
There is 1.75" inside of tire to spring

Your current back spacing is 3"

You need to move the wheel /tire combo inboard by 1.25 inches to clear the fender lip.

You have 1.75" on the inside.

So when you get your new wheels with 4.25 back spacing (existing 3 plus the 1.25 you need to move the tire) you will have 1/4" on the outside and 1/2" on the inside clearance.
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This sounds right. I do have the 3 in backspacing cube currently and the numbers you have were pretty much right on. I did look up the 15x7 and they show 4.3 backspacing so looks like that's what I need.
 
And then there was the perfect "Dart" Tire/Rim/ Spring combination.

Big Block short leaf on the bottom of the original stack.

Screenshot_20220421-003124_Gallery.jpg


Gave a 2" Lift over stock.

If you start adding "Big Girls sit in the Back", then you add the Monroe Max air shocks to keep the sidewalls off the outer inner wheel house, and still have a nice ride. Big girls not out for the night, let the air pressure down and it's back to the normal 2" lift with the nice ride.

Dial it in, it's kind of an art getting the right height and a good ride to go along with it.

Super Stock Leafs ride like a Truck with the lift they provide.

☆☆☆☆☆
 
George Jets said:
And then there was the perfect "Dart" Tire/Rim/ Spring combination.

Big Block short leaf on the bottom of the original stack.

View attachment 1716095165

Gave a 2" Lift over stock.

If you start adding "Big Girls sit in the Back", then you add the Monroe Max air shocks to keep the sidewalls off the outer inner wheel house, and still have a nice ride. Big girls not out for the night, let the air pressure down and it's back to the normal 2" lift with the nice ride.

Dial it in, it's kind of an art getting the right height and a good ride to go along with it.

Super Stock Leafs ride like a Truck with the lift they provide.

☆☆☆☆☆
Click to expand...
What size tires and rims are you running. I do like the look and the this ride height is what I am looking for especially living in illinois as it has an illegal suspension law, ask me how I know lol.
 
14 x 7 Aluminum Slots with BF Goodrich tires, white letters in.

Can't remember the tire size, but look up the 14s and see what is available yet on the BFGoodrich web site. Just guessing 235 60 14"s ???

Old school, the way they did it back in the day.

☆☆☆☆☆
 
moparfanatic56 said:
10x2.5
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FYI

That you have 10x2.5 brakes says you have BBP spaced axles and that means your axles push your wheels out a small amount ( might be around 1/4" )

That does not mean anything now for your current setup, just something to know.


just do your measuring and THEN order what will fit.
 
Also be aware that backspace and offset are NOT the same thing. And also that wheel width is measured from the inside of the beads, so a 15x7 aluminium wheel will be 8" wide.
Excuse me if you know all this already, just trying to help......
 
The wheels you currently have (assuming steel Cragar SS's) are 8.5 wide. With 3.5 backspace, they are -19mm. offset (3/4"). What you probably need is a wheel with zero offset, or a small + number. With the pattern change, and wider brakes, I would lean toward a 10mm positive offset.
 
I'm running 14 x 7 wheels and 245-60-14 tires on two of my 70 Darts, but I could never get enough clearance inside next to the springs, without moving the springs in 3/4 inch with the kit that MP designed and others now make. Even with custom offset wheels, once I had the clearance for the outside at the fender the tires ran up against the springs...
 
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