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Discussion Starter · #1 ·
I have ARE Torque Thrust D VN105D wheels on my 65. I dont like them because I am one of those guys that like shiny things. Issue is that they are TIGHT in the rear wheel wells. The rims are 15X7 and the tires are M&H Racemasters G60/15. ARE website says the wheels are -6 offset. Don't understand because its not 6" and 6mm is hardly anything.
I would'nt mind getting the same rims in chrome/polished, but they dont make them. I don't think I can fudge with the size because it is so tight. I have measured the backspacing on my own, and found sizes that are close, but unless its exact Im afraid to buy them.

Heres my question....
Can I fudge with the size as far as getting a wider rim, and compensate with the backspacing to equal whats on there now? I just confused myself. LOL
 

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I have ARE Torque Thrust D VN105D wheels on my 65. I dont like them because I am one of those guys that like shiny things. Issue is that they are TIGHT in the rear wheel wells. The rims are 15X7 and the tires are M&H Racemasters G60/15. ARE website says the wheels are -6 offset. Don't understand because its not 6" and 6mm is hardly anything.
I would'nt mind getting the same rims in chrome/polished, but they dont make them. I don't think I can fudge with the size because it is so tight. I have measured the backspacing on my own, and found sizes that are close, but unless its exact Im afraid to buy them.

Heres my question....
Can I fudge with the size as far as getting a wider rim, and compensate with the backspacing to equal whats on there now? I just confused myself. LOL
I'm guessing they're tight on both sides so off-set isn't going to change that. The widest tire that will fit in the 64/65 wheel well without rubbing is usually 225/60-15 (on a 15x8 wheel) but some have squeezed in a 235 on the same wheel. I'm not exactly sure on the actual width in inches on both the metric tires or your G60 but I'd guess they're wider. I think your problem isn't the wheel as much as it is the tire. How wide are they at the widest point? If you have a tape measure that has metric as well get that measurement and compare them.

John
 

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Discussion Starter · #3 ·
Im not 100% sure, but I believe the guy messed with the rear length when he put the 9" in. Guess I will have to experiment
 

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I have ARE Torque Thrust D VN105D wheels on my 65. I dont like them because I am one of those guys that like shiny things. Issue is that they are TIGHT in the rear wheel wells. The rims are 15X7 and the tires are M&H Racemasters G60/15. ARE website says the wheels are -6 offset. Don't understand because its not 6" and 6mm is hardly anything.
I would'nt mind getting the same rims in chrome/polished, but they dont make them. I don't think I can fudge with the size because it is so tight. I have measured the backspacing on my own, and found sizes that are close, but unless its exact Im afraid to buy them. Every car is a little different but your best bet is a 5" backspace wheel in a 8" wide wheel With the stock length housing.

Heres my question....
Can I fudge with the size as far as getting a wider rim, and compensate with the backspacing to equal whats on there now? I just confused myself. LOL
Wheels for less has a 16x8 TT 2 that is polished with a 4.89" backspace, I have a set of these for our 64 Comet with 245-50-16 tires that clear with no mods and stock length rearend. On my 65 Falcon I have 15x8 TT 2 with 4.5" backspace but the rearend is narrowed 1/2" on each side using a 235-60-15 tire. I also have a 9" rear in both cars that use the smaller leaf spring plates as compared to the stock 8" rear end leaf spring plates. Bottom line is to run a 8" wheel you need at least 4.75" and 5" of backspace would be better. Also look into Eagle wheels they may have the backspace you need and make a polished wheel like the Torq Thrust.
 

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Discussion Starter · #5 · (Edited)
Here are the specs on my tires

  • Tread Width: 7.8"
  • Section Width: 10.3"
  • Diameter: 26.2"
  • Circumference: 82.3"
  • Rim Size: 7.0"
  • Code: MSS-003
  • Compound Type: 703 **(NOTE) TIRES ARE ONLY SOLD AS PAIRS. YOU MUST PUT AT LEAST 2 IN THE QUANTITY BOX.**



 

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Discussion Starter · #6 · (Edited)
The rims do not look bad in the pictures, but they are pretty bad looking in person. The guy that had the car before me did not take good care of them.


Ok, whose good with numbers?
From what I read, offset is the difference from the dead center of the rim to back of where the rim mounts. Backspacing is from the rear of where the rim mounts to the outer edge of the rim.
If my 7" rim is -6mm offset, what is my backspacing?






 

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25.4 mm in an inch....7 x25.4=177.8 DIV. by 2= 88.9 Subtract 6mm = 82.9 and convert back to inches, Divide by 25.4=3.26" Now account for the lip of the bead (.25 ?) My guess is you have a 3 1/2 or 3 3/4 inch backspace.
I use a 4.5 " but 5 "would be better. Also not a stock rear end and can't remember off hand the length.
How do you attach pic? I have good one showing how to find what you're needing to do to give you confidence when ordering.
 

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Discussion Starter · #8 ·
Got an email back from American Racing and they say the back spacing is 3.8 Guess that's what I need to find
 

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Got an email back from American Racing and they say the back spacing is 3.8 Guess that's what I need to find
Your backspacing is 3.75" That is a standard wheel backspacing on the TT D 7" wheel. Your offset of -6 on a 7" wheel is 3.75" of backspace. You need a 8" wheel with that tire size. If you have the stock length rear housing you need at least 4.75" backspace and 5" would be better, that is about the max you can go without relocating the leaf springs. My 65 Sprint has the rearend narrowed 1/2" on each side and I run a 15x8 with 4.5" of backspacing and 235-60-15 Drag Radials. If my housing was not narrowed I would run a 5" backspace wheel.
 

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That g-60 is a very wide tire around 260mm. The 235-60-15 M/T drag Radial would fit your car better on a 8" rim. How much room do you have from the tire sidewall to the leaf Spring?
 

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The easy way to figure backspace, is that you add 1" to the wheel width (0.5"/13mm for each lip). For a 7" wheel, that would be 8" total width. Half of that is the zero-offset centerline, or 4" in your case. 6mm negative offset (-6mm) is .236", and negative is towards the center of the car.

So, a 7" wheel with -6mm offset would be:

7" + 1" = 8" (total width)
8" / 2 = 4" (zero offset)
4" - 0.236" = 3.764" (backspace)

That's just over 3-3/4", but actually rounds-up (by 36 thousandths) to the even 3.8" backspace AR quoted.

HTH

David
 

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Discussion Starter · #13 · (Edited)
Here are some pictures. I would assume that changing the rim from 7" to 8" would not effect the width of the tire. However if you look at the tire specs I posted earlier, it says the rim width is 7". So I do not know if I could go 8". From the pictures, what do you think I should try. I wish there was someone local that I could try their set up in my wells.
In the one picture you can see I have 1.5" from the rim to the spring. You can really see how much wider the tire is compared to the rim. These pictures are also without any weight on the tires. Down on the ground they are way up in the wells. A guy told me just to get the 15X7 with 3.5" backspacing with a 1/4" spacer. Then it will the same as the Torque Thrusters 3.75". Really want to get a set of Weld Prostars
 

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You have the 3.75 backspace with 7" wheel right? To get the same tire location with an 8" wheel you need the backspace to be 4.25 and I'm thinking you have more room to go inward than outward right? If so get the 8" with 4.5 to 5" backspace Get a piece of paper and a straight edge and start drawing some lines to scale until it makes sense, that's what I did because that's the only way my brain works! I'm thinking the spacer thing that guy was talking about will put you in the wrong direction.
 

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Discussion Starter · #15 ·
I really don't have room to go either way unless I cut out the inner wheel well. Now you got me thinking about that spacer being the wrong way.
 

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If you want to use an 8" wheel get a 4.25 backspacing and the tire will be in the same position as the 7" with the 3.75 BS. It's really confusing but drawing a picture will help visualize it. Can anyone else confirm this?
 

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8-7=1 / 2=1/2+3.75=4.25. I can't find the divide sign

You're also adding 1/2 inch to the outside, so check your clearance there. On a stock 8 inch I was running 4.5 inch b s on a 7 inch rim. didn't have much clearance on either side with a 225.60.15. I now run a 5 inch back space on a 9inch rear end. Same tire. 15 inch rims with 5 inch back space are not in everyone's stock pile.
 

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Discussion Starter · #18 ·
I have room to move on the rim, BUT the tire must remain in the exact same position. However, I have yet to see a 8" Weld in a 4.25" backspacing.
 

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Here are some pictures. I would assume that changing the rim from 7" to 8" would not effect the width of the tire. However if you look at the tire specs I posted earlier, it says the rim width is 7". So I do not know if I could go 8". From the pictures, what do you think I should try. I wish there was someone local that I could try their set up in my wells.
In the one picture you can see I have 1.5" from the rim to the spring. You can really see how much wider the tire is compared to the rim. These pictures are also without any weight on the tires. Down on the ground they are way up in the wells. A guy told me just to get the 15X7 with 3.5" backspacing with a 1/4" spacer. Then it will the same as the Torque Thrusters 3.75". Really want to get a set of Weld Prostars
Going from a 7" wide wheel to a 8" wide wheel will change the width of tire !!

For every 1/2 inch change in wheel width you will have a .2 inch change in tire section width.

So if you go from a 7 inch wide wheel to a 8 inch wide wheel your tire section width will be .4 inch wider.

Your tires now have a section width of 10.3" on your 7" wheels, going to 8" wheels your section width will go to 10.7" about 1/2 inch wider.

Going with the Pro Stars 15x7 with 3.5 back spacing will move your tire/wheel a 1/4 inch out closer toward the fender, 1/4 inch away from the spring/inner fender. Basically will lose 1/4 inch clearance at qtr panel and gain 1/4 inch clearance on inside. Adding a 1/4 inch spacer With the Pro Star 15x7 3.5 BS will move it 1/2 inch closer to qtr and give you a 1/2 inch more clearance on inside.

What clearance do you have now between tire and qtr panel?
Lou
 
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