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Discussion Starter · #1 ·
Afternoon all,

I am looking at purchasing new wheels for the XL & honestly dont know the exact specifications (ie: offset, bore diameter, backspacing, bolt circle etc.)

US Imperial measurements would be fantastic :)

Many thanks again for assistance.
 

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Discussion Starter · #3 ·
Unfortunately, that is not the info im looking for, but thanks anyway :)

I need the specs of the wheel itself, not tyres. Places such as Summit, etc detail the bolt circle, offset, etc in Inches. And I have no idea which one is correct for mine.

I suppose I could always go out & measure it all myself, but a convenient reference I can bookmark would be better.
 

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Scott, if that's you then all you need to know is pre AU. I think your 70 is still 5x4.5 as my 71 rotors on my 65 certainly are. Anything that fits your Fairlane should also fit the Gal...
 

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Further, just to lay it out...

Bore centre - 70/71mm diameter
Bolt pattern - 5 x 4.5" (which is 114.3mm)
Backspace - depends, but in context my 7" rim has a 3.75" backspace and my 8" rim has a 4" backspace. For offsets there are loads of sites that will assist you in turning one into the other.

The alternative is to plug your car into Summit or Jegs and search for wheels that fit according to them. That way you can easily find out bolt patterns and hub centre bores. Offset and backspace will depend on the rim specifically as they're not all the same. And your car of course. Perhaps danv can help as he's got a 70 and has done a few wheel swaps over the years if I recall correctly.
 

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Discussion Starter · #6 ·
Further, just to lay it out...

Bore centre - 70/71mm diameter
Bolt pattern - 5 x 4.5" (which is 114.3mm)
Backspace - depends, but in context my 7" rim has a 3.75" backspace and my 8" rim has a 4" backspace. For offsets there are loads of sites that will assist you in turning one into the other.

The alternative is to plug your car into Summit or Jegs and search for wheels that fit according to them. That way you can easily find out bolt patterns and hub centre bores. Offset and backspace will depend on the rim specifically as they're not all the same. And your car of course. Perhaps danv can help as he's got a 70 and has done a few wheel swaps over the years if I recall correctly.

Thats the information I needed. Thanks Nick.
 

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Discussion Starter · #7 ·
Ok, I done the best simple math I can, so heres the story;

I want Cragar Super Spoke Wheels for it. In 15x7, and maybe 15x8.

Ive found correct bolt circle, offset & backspace specs. However, the Centre Bore diameters ive worked out are too big.

I need 70/71mm & the smallest I could find is 3.3" (84mm). I really do not want to put sleeves on it, so does Cragar make this wheel in 70mm spec? Or will I have to go custom?
 

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I think you'll find that those particular Cragars are a truck rim, which may explain the larger hub centre diameter. Could be wrong, but they look that way.

If you go for them, I know a local engineering mob who can machine you up spacers. Although with the rim being steel, there wouldn't be much "meat" to support such a spacer.

As for whether they come with a smaller centre bore, I think you'd have to ask Cragar.
 

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Discussion Starter · #9 ·
Story of my life; wanting the ones that arent suitable for my car straight off the shelf :cry:
 

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If it's these wheels you are after in the link here.....
Cragar 3305712 - Cragar Chrome Super Spoke Wheels - Overview - SummitRacing.com
....then I don't think you'll have too much of a problem.

Firstly, the prices is very good compared to what we have down here.
Secondly, they will look pretty good, especially compared to your black paint.
Thirdly, I believe there are two types of load bearing fitments. One is on the studs, and the other is on the hubs. By looking at the specs of the wheels, I believe these are the stud type because it says they are not hub centric, so to me it means that the studs will locate and take the weight of the car. If they were hub centric then it would say so.

Even if I am wrong in my interpretation, I would reckon that most of the cars out there today with aftermarket wheels would be using wheels with larger center holes than what the hubs are. Two of my cars are, and I have never had a problem.
 

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I think you'll find that those particular Cragars are a truck rim, which may explain the larger hub centre diameter. Could be wrong, but they look that way.

If you go for them, I know a local engineering mob who can machine you up spacers. Although with the rim being steel, there wouldn't be much "meat" to support such a spacer.

As for whether they come with a smaller centre bore, I think you'd have to ask Cragar.
Those wheels will fit fine..As was stated above the Cragar S/S wheel locates off the wheel studs and uses mag wheel lugnuts. Note there are different length shanks on those lugnuts, get the correct length and all will be good. The wheel dealer will know which length lugnuts you need.
 

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Discussion Starter · #12 ·
Thankyou all so much for the info.

Im wondering what is the widest tyre that can be safely fitted to 7". I keep getting different answers from people.

Some say 235 fits, some dont.
 

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I've had 265s on 7" rims.
 

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Thankyou all so much for the info.

Im wondering what is the widest tyre that can be safely fitted to 7". I keep getting different answers from people.

Some say 235 fits, some dont.
A 255/60 looks nice, I think a 275 would be safe, but theres gonna be a pretty big sidewall bulge. 295/50 will work on an 8" rim.

Fenderwell and wheel lip clearance are going ot be the limiting factors, finding someone with a car like yours and looking at them are the best guide to max tire size unless your tire shop will test fit tires, most won't.
 

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If it's these wheels you are after in the link here.....
Cragar 3305712 - Cragar Chrome Super Spoke Wheels - Overview - SummitRacing.com
....then I don't think you'll have too much of a problem.

Firstly, the prices is very good compared to what we have down here.
Secondly, they will look pretty good, especially compared to your black paint.
Thirdly, I believe there are two types of load bearing fitments. One is on the studs, and the other is on the hubs. By looking at the specs of the wheels, I believe these are the stud type because it says they are not hub centric, so to me it means that the studs will locate and take the weight of the car. If they were hub centric then it would say so.

Even if I am wrong in my interpretation, I would reckon that most of the cars out there today with aftermarket wheels would be using wheels with larger center holes than what the hubs are. Two of my cars are, and I have never had a problem.
Aftermarket wheels are universal so the center bores are big to accommodate several different vehicles. That being said most aftermarket wheels are lug-centric meaning they rely on the wheel studs for centering. The fact that a wheel is hub centric has nothing to do with load bearing, it is simply for centering purposes. It is always the clamping force (created by the wheel lug torque) that supports the load. There are hub-centric rings available from Coyote, Excalibur, etc but these are more tailored to late model vehicles. Haven't ever seen one for a Cragar application, especially on a vintage car. I'm sure they could be machined if desired though. Older vehicles seem way less sensitive to vibration than the tin can econoboxes of today that transmit every irregularity to the driver.
 
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