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  #25  
Old 04-14-2016, 01:02 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

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Originally Posted by ARWK2OL View Post
I have an 11 Overland with the quadra lift. I have the Llyms module on it. It gives 1.25" or 2" of extra lift depending on the setting. I am wanting to run a 275 70 18 tire on a wheel with +34 offset. I don't mind trimming the felt, bolt or pinch welds. The truck won't be taken off-road with this setup. I plan on something closer to stock for that. The tire is basically a 33.2x10.8". Any thoughts or pics would be great. Thanks.
to successfully run a 33"tire is going to require you to have your quadra lift setup sitting at what was OEM max height. I understand how the Llyms module works, and basically youve just tricked it in to being lifted to or1 at normal, orII at the or1 setting and it may or may not lift beyond orII (I hope not).

if you always leave it in or1, for orII factory lift sure..in theory it works. if the specs on the manufacturer you want truly are 33.2 (mine are 32.8) if you roll your pinch and pin back the felt.. you 'should' be good on that 34 offset, if its an 8.5"wheel we are talking about. if its 9 or wider, youll want a lower offset.

honestly, i do not recommend you do a 33 on QL, even with the Llyms. You know the ride sucks when you are lifted up at the 2.5" setting. And thats honestly what you need to be sitting at, at all times for that tire to work for you. Id get a nice beefy looking 32-32.4" tire and call it good. IMO

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  #26  
Old 04-15-2016, 11:54 AM
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Re: Offset - Backspace - ideal fitment - Calculation chart

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Originally Posted by alludc View Post
to successfully run a 33"tire is going to require you to have your quadra lift setup sitting at what was OEM max height. I understand how the Llyms module works, and basically youve just tricked it in to being lifted to or1 at normal, orII at the or1 setting and it may or may not lift beyond orII (I hope not).

if you always leave it in or1, for orII factory lift sure..in theory it works. if the specs on the manufacturer you want truly are 33.2 (mine are 32.8) if you roll your pinch and pin back the felt.. you 'should' be good on that 34 offset, if its an 8.5"wheel we are talking about. if its 9 or wider, youll want a lower offset.

honestly, i do not recommend you do a 33 on QL, even with the Llyms. You know the ride sucks when you are lifted up at the 2.5" setting. And thats honestly what you need to be sitting at, at all times for that tire to work for you. Id get a nice beefy looking 32-32.4" tire and call it good. IMO

Alludc, thanks for the advice. The lift on medium is actually .75" lower than the factory OR2 setting. You would think it would ride rough, but it actually feels similar to a sports car, definitely stiffer but not bad at all. I'd compare to riding in a newer Camaro or Mustang. I actually like the ride, but I certainly can see how many,if not most Overland drivers would not. I did have my mind pretty well made up, but you made me step back and rethink my setup. Just wanted to say thanks again for the knowledge and taking the time to chime in. I'm still not sure which way I'll go now, but I still have a month or so before pulling the trigger on wheels and tires.
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  #27  
Old 04-18-2016, 05:14 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

So what is the wheel backspacing on a stock Jeep WK2 20x8 wheel? I cannot find this listed and one would think this would be in the wheel spec or easily found as it is a constant
Without taking the wheel off and measuring is it to be assumed
1/2width + offset +1/2" for wheel lip?
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  #28  
Old 04-18-2016, 05:21 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

stock offset is 56 on the 20x8
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  #29  
Old 04-18-2016, 06:05 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

Stock altitude rims
20X8
Backspace is not listed.
To use the chart you need to know backspace.
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  #30  
Old 04-19-2016, 12:45 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

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Originally Posted by VWTG View Post
Stock altitude rims
20X8
Backspace is not listed.
To use the chart you need to know backspace.

the chart I posted is for offset and backspace. its all there, but anyway....stock altitude wheels are 6.70" backspace
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  #31  
Old 04-19-2016, 02:52 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

I believe I have miss Interpreted the original post and chart purpose.
I am trying to figure out how to fit 33" tires on the WK2. Using the stock Wheels
20x8
56. 4mm offset
6.72" backspace.
If I follow the chart and run the math it concludes optimal offset is 56.4mm @8". The factory offset.
Yes this will change for varying wheel width and backspace but it does not really confirm 33" fitment does it?
How did you come up with the wheel/tire setup? Was it simply trial and error or previous experience?
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  #32  
Old 04-19-2016, 03:04 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

Quote:
Originally Posted by VWTG View Post
I believe I have miss Interpreted the original post and chart purpose.
I am trying to figure out how to fit 33" wheels on the WK2. Using the stock rims.
20x8
56. 4mm offset
6.72" backspace.
If I follow the chart and run the math it concludes optimal offset is 56.4mm @8". The factory offset.
Yes this will change for varying offset and backspace but it does not really confirm 33" fitment does it?
How did you come up with the wheel tire setup? Was it simply trial and error or previous experience?
Trail and error by way of mock ups, and years with Discount Tire Direct along with 20+years of modding my wheels & suspension setups.

you are misreading though. my post states 20x8.5 +31 is ideal. if you use the chart, youll see that (32mm is shown, close enough) equates to 38mm on a 8.0" width. so, technically..that should be ideal. how do you get 38mm on a stock wheel...well you dont. there isnt a 18mm spacer. so, best case scenario is you find a 1"spacer (25.4mm) and you end up with a 31 offset on your 8"wheel. That 31 would equate to a 25mm offset on my 8.5" wheel. Its not exact, but its close....and it MAY work rub free. If it does rub, will be quite minimal and easy to correct. ***this will depend also on the tire itself. is it true 33? or is it 32.6, 32.8, 33.4? Changes from manufacturer to manufacturer.
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Old 04-19-2016, 03:18 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

I definitely misunderstood. The best part of this is I have your set up to reference and with some light math, I can air on the side of caution.
Slightly off subject question referencing your set up.
Why does atturo call your TIRE 33" and the 285/55 not. Actual height difference is 0.2"?
So essentially what criteria is it that makes a tire a 33"?
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  #34  
Old 04-19-2016, 03:21 PM
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Re: Offset - Backspace - ideal fitment - Calculation chart

tons of people make 33, 35s, 37s, etc that are not. I dont know their reasoning behind it, although in most cases...those designated with a 33, 35 etc are usually extra ply LT tires and most 285 type sizes are not LT. Again, this is subjective as the Atturos list the 285 55 also as a LT, but the 275/55 is not. strange game isnt it?

on another tire note, did you know that the utqg (mileage rating) on the tires dont mean squat? this isnt a standardized number. a 400 treadwear on one company could very well be a 200 from another.
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  #35  
Old 04-20-2016, 04:09 AM
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Re: Offset - Backspace - ideal fitment - Calculation chart

I have a '14 with QL and with stock 20's and 1.25" spacers. That puts me at +24 mm of Backspacing.

At +24 bs, which will fit better, 275/55 or 285/50? Will both?

The 285's will go out farther toward the fender and might not "tuck in" to the fender under compression.
The 275's will clear the fender better but have a larger diameter.
I'm not sure which will be a closer fit or rub.

Can anyone share who has had one of these set ups?

Planning on nitto G2's.

Thanks!
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  #36  
Old 04-20-2016, 04:15 AM
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Re: Offset - Backspace - ideal fitment - Calculation chart

Quote:
Originally Posted by rhino8888 View Post
I have a '14 with QL and with stock 20's and 1.25" spacers. That puts me at +24 mm of Backspacing.

At +24 bs, which will fit better, 275/55 or 285/50? Will both?

Will the 285's go too far out hitting the fender under compression or will they fit better than the 275's because of the smaller diameter?

Can anyone share who has had one these set ups?

Planning on nitto G2's.

Thanks!
285s will most likely rub, so will 275s I think. I have 275/55/20s and 34mm offset and mine were hitting a couple spots of metal that had the felt pinned to it. I took out the clips and bent the metal back. Now they fit by millimeters.
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