Bigger Wheels on 460

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Jdring
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I got a nice set of 265/60 R18 wheels (from a G350 I think) and want to try them first on my 460.

Will I need spacers and longer wheel bolts to prevent rubbing/contact on the inner sides?

Obviously no electronics or ESP to worry about, and the slightly bigger circumference may add a little bit of top-speed for a more comfortable 3k rpm running.

I thought I would calculate that and to start there is a good explanation of Tyre Size standard here:

https://www.uniroyal-tyres.com/car/tyre-guide/tyre-knowledge/what-does-tyre-size-mean 

So the circumference of my current 460 wheels (225/R75 R16) would be:

75% x 225 = 169mm.  Plus half the rim diameter = R16 / 2 * 25.4 = 203mm.   168+203 = 372mm Radius (744mm diameter)

Interestingly, measured diameter with a tape and it was about 720mm, so close !

For the new tyre (265/60 R18):

60% x 265 = 159mm.  Redius = R18 / 2 x 25.4 = 229mm.  159 + 229 = 388mm  (775mm diameter)

Measured at 750mm, so the same undermeasurement.

 

Lets go with the calculated diameters:

1 wheel revolution = Pi x Diameter = 3.1416 x 744 = 2.34m  (for the 460 wheel)

1 wheel revolution = 3.1416 x 775 = 2.43m  (for the 463 wheels) - not that different

2.43/2.34 = +3.8%  per revolution.

Now the guessing part... I recall that the 460 does about 3,800rpm at 60mph currently.  So with the 3.8% increase in wheel, that will increase to 62.28mph.

So after all that... bugger all noticeable increase!

 

Anyway - they will look nice - anyone got wheel spacers and bolts?   

 

G-Restorations
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Re: Bigger Wheels on 460
Hello John I've been running these wheels on my 460 for the last 6 years. To get the same offset as the original wheels you will need 20mm spacers. This will put no more load on your wheel bearings than the original wheels as the Centreline if the wheel is the same. So that the wheels lined up with the 463 arches I'd fitted I used 40mm spacers. This isn't ideal the wheel bearings needed regular adjustment and puddle steer was a bit scary Saying that though the handling was really improved. I'd really recommend continental 4x4 LX tyres. Gordon
Jdring
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Re: Bigger Wheels on 460

I'm getting Toyo Open Country A/T 265x60 R18 tyres tomorrow.  The spec seems really good and apparently better wearing than the Yokohama's I currently have.  Top rating for grip and quiet too, plus the sidewalls look good.

I opted out of getting the slightly bigger wheel (265 x 65) because the difference was marginal and the tyre expert said not to bother (OK I wimped out).

 

 

Jdring
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Re: Bigger Wheels on 460

Here's the end result.  Surprisingly, the nobbly tyre pattern is rated quieter than most.  Not something you can really tell by ear.  I kind of wish I had gone for the 65% profile, bigger tyre, despite what I was advised, but at least with this all the speed and electronics will be happy.   As above, it makes about 4% difference.

 

GWOA EDIT:  Need to check the above calcs and there is a ready made site to help here: https://www.tyresizecalculator.com/tyre-wheel-calculators/tire-size-calculator-tire-dimensions 

 

Jdring
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Re: Bigger Wheels on 460

Oh, and just to complete this, the wheels went back on the 463, not the 460 in the end.  I didn't have the 25mm spacer or longer wheel bolts.   When I get those, the old alloys from the 463 will get tried on the 460.

prwales
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Re: Bigger Wheels on 460

the 463 wheels wont look right on the 460 without spacers