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Official 6-Lug Re-drill Thread: Now in the USRM!

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close, your on the right track. for example an 175R/75/15. the tire is 175mm wide, the side wall is 75% of that, and it is radial tire on a 15" wheel.

 

 

correct, and a 175R/70/15 would be the same width, but only 70% for the sidewall height, making it a slightly smaller tire, even tho it will still fit on the same rim.

 

the contact patch is determined by the first number - the width of the tire (and proper tire inflation) - the side wall height really has very little to do with it. a taller sidewall may "look" wider (balloon out more, depending on wheel width), but it doesnt really affect the contact patch all that much.

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Since I'm lazy, who's trying to sell me all 4 redrilled hubs? :3

 

probably not anyone in this thread, there all on our cars. :lol:

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Here's my 87 with b2300 mazda wheels. One with the wheel fully stuffed - mounted everything but the spring & jacked up until it lifted both wheels.

4" SJR lift, 27x8.50x14s

 

OOPS! No pics!

Edited by czny
spelling

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correct, and a 175R/70/15 would be the same width, but only 70% for the sidewall height, making it a slightly smaller tire, even tho it will still fit on the same rim.

 

the contact patch is determined by the first number - the width of the tire (and proper tire inflation) - the side wall height really has very little to do with it. a taller sidewall may "look" wider (balloon out more, depending on wheel width), but it doesnt really affect the contact patch all that much.

 

 

That's what I'm getting at, even if the tread width on the tire is marked identically, the tire with the shorter sidewall will be marginally wider.

 

MARGINALLY, but still a measurable difference. I do not know if this is true for ALL tires, but all that I have measured, it has held true for.

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That's what I'm getting at, even if the tread width on the tire is marked identically, the tire with the shorter sidewall will be marginally wider.

 

MARGINALLY, but still a measurable difference. I do not know if this is true for ALL tires, but all that I have measured, it has held true for.

 

you might be dealing with over inflated tires. because if they are both 235/75/15 and 235/70/15 they should both be 235mm wide, but different brands might be off a bit.

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That's what I'm getting at, even if the tread width on the tire is marked identically, the tire with the shorter sidewall will be marginally wider.

 

MARGINALLY, but still a measurable difference. I do not know if this is true for ALL tires, but all that I have measured, it has held true for.

 

Tires do not mark the tread width. They mark the section width. The tread width is almost always narrower than the section width.

 

tireDiagram.gif

 

The section width of a tire will vary based on inflation pressure, but more significantly, will vary based on the rim width. The section width as marked on the tire is based on the tire being mounted on a specific width of wheel. If you mount the tire on a wheel of a different width than what the manufacturer used, then your actual tire width (what you measure) will be different than the width marked on the side of the tire.

 

It is also true when comparing tires of different sizes, styles, or manufacturers, that the manufacturer(s) may have used different width wheels when marking them. There are standardized rim widths that the manufacturers use for measuring, but they are standardized per tire size, so the baseline rim might not necessarily be the same if you are comparing different sizes of tires. This means that it is entirely possible for two tires, of the same marked section width, to have different actual widths when mounted on your wheels.

 

//edit: There is some manufacturing tolerance as well. So two tires of the same size from different manufacturers or of different styles won't necessarily measure exactly the same either.

Edited by Red92

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Tires do not mark the tread width. They mark the section width. The tread width is almost always narrower than the section width.

 

tireDiagram.gif

 

The section width of a tire will vary based on inflation pressure, but more significantly, will vary based on the rim width. The section width as marked on the tire is based on the tire being mounted on a specific width of wheel. If you mount the tire on a wheel of a different width than what the manufacturer used, then your actual tire width (what you measure) will be different than the width marked on the side of the tire.

 

It is also true when comparing tires of different sizes, styles, or manufacturers, that the manufacturer(s) may have used different width wheels when marking them. There are standardized rim widths that the manufacturers use for measuring, but they are standardized per tire size, so the baseline rim might not necessarily be the same if you are comparing different sizes of tires. This means that it is entirely possible for two tires, of the same marked section width, to have different actual widths when mounted on your wheels.

 

//edit: There is some manufacturing tolerance as well. So two tires of the same size from different manufacturers or of different styles won't necessarily measure exactly the same either.

 

Awesome information, and I already understood the difference between tread width and section width, but was trying to prevent the muddying of the waters by adding yet another term to the mix.

 

Let me refine my statement even more:

 

Taking the EXACT SAME model, manufacture, section width, rim width and diameter, the tire with the shorter sidewall WILL be slightly wider than the taller version.

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Yeah I think the only solution is to wait a few months and go 5 lug lol

 

why do you say that? it is alot more work, and cost more, and i like the selection of wheels for 6 lug preferably.

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why do you say that? it is alot more work, and cost more, and i like the selection of wheels for 6 lug preferably.

 

You can run Impreza struts and driveline then. The XT6 knuckles are what the EJs were based on and well worth it!

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unless you are wanting more performance, then drill your hubs/drums out to 6 lug. if you want impreza performance, and five lug wheels then i guess...

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^^^ this is what determined my choice to go five lug instead of six. Opens up more options than just wheels.

 

From running Outback struts to Impreza Tokicos, not to mention any 5x100 wheel on the market, the 5-lug swap is worth it if you can come up with the Parts. THe XT6 hubs are kinda like gold to the Aussies since they never had the XT6 (Although they did get the Vortex) but in limited numbers.

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i would do it, but i plan on getting an 06' wrx in the next couple of years, so its not worth it for me.

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i would do it, but i plan on getting an 06' wrx in the next couple of years, so its not worth it for me.

 

Why not have two Cool Subies? Hell, I have 3 vehicles. No crime in that ;)

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Why not have two Cool Subies? Hell, I have 3 vehicles. No crime in that ;)

 

yeah buddy! if i could have these three ( witch i will one day ) i would have my current car ( 85 wagon, soon to be lifted 2" ) my next car ( 06' wrx, turbo hatch back ) and if i find one ( 78 wagon, cherry red )

 

one day......

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yeah buddy! if i could have these three ( witch i will one day ) i would have my current car ( 85 wagon, soon to be lifted 2" ) my next car ( 06' wrx, turbo hatch back ) and if i find one ( 78 wagon, cherry red )

 

one day......

 

I think the '78 Wagon will be the most hard to find ;) Although, it would probably be the cheapest on the list!

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ya i paid 500 for my car up front, and since then have put about 3k into it. i probably wont get what i want out of that 06' wrx for less than 15k ish. and i dont even know where to look for a 78 besides japan, lol

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I dont even know where to look for a 78 besides japan, lol

 

The great state of Washington, they seem to have everything.... :drunk:

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touche...

 

Lol! Well. They junk cars that are 10 times cleaner then what I'm trying to save. Outstanding isn't it? I can't get over how many clean running Subarus they junk out west because it has a rust hole in the door about the size of a golf ball... :horse:

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Lol! Well. They junk cars that are 10 times cleaner then what I'm trying to save. Outstanding isn't it? I can't get over how many clean running Subarus they junk out west because it has a rust hole in the door about the size of a golf ball... :horse:

 

im tellin you man, get out here. drive back. all smiles.

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