Hi everyone,

Has anyone fitted 285/65R20s BFG AT KO2 to their L494?

Will they fit without rubbing?

Thanks --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport Supercharged V8 HSE Dynamic



Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

anyone? --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport Supercharged V8 HSE Dynamic



Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

You're quite possibly the only L494 owner on here that uses his vehicle off road in any real way, so the only one likely to have even considered such a tyre. Unlikely to get much of a response because of that, sadly. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Yeah, I figured as much.

I was told on FB groups that 285 is too wide and will rub on the inside wheel arch, so it looks like 275 is the max.

I do have options of a slightly used set of 255/60 Goodyear Wrangler AT Adventure that came off a brand new Defender, so that will probably be the one to go for.

These will give me a sidewall increase of 12.75mm, and overall diameter of 32.05". I'm sure going from the 255/55R20, which is 31.04", to 32.05" will be fine. --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport Supercharged V8 HSE Dynamic



Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

That's only half an inch which you should be able to check by applying full lock when in access mode. You might need access to a friendly garage with a ramp to get a good look, of course, as when it's hunkered down on its belly you'll struggle to see and measure the inside otherwise. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

naks wrote:

I was told on FB groups that 285 is too wide and will rub on the inside wheel arch, so it looks like 275 is the max.

If driving off road on sand or soft ground would you not need a wider tyre rather than a narrower one to increase the footprint of the tyre to give it more traction and stop it sinking into the sand etc. Although deflating the tyres slightly I imagine would have a similar effect.

Cheers
Col

Good point.
With wider tread, you gain the contact area and lower the pressure the car exerts on the surface. The car sinks less and that benefits the ability to move. Good (to an extent) in sand/mud situations.
With narrower tread, you up the pressure the car exerts on the surface. While more prone to sinking in mud or loose sand, you benefit from more force being transmitted to a unit of surface, so even a smallest grippy area under the tyre will be used.
This is obviously a "to each their own" situation, as there are various scenarios for various environments and various vehicles. The tyre size chosen by LR is not a purely esthetic choice, it is also a compromise for optimum traction. If I was looking for maximum "traction" (defined by force x coefficient of friction) I'd go narrower than stock, but if we're talking not sinking in a mud pit, a wider tyre may be beneficial.
But to make actual sense, a mud/sand oriented tyre is also taller (and often with some tread on a part of the sidewall). The mud driving pros chose wide but tall tyres, as they want to minimize the pressure on the surface. In order to get more traction, the way to cheat the book is by using the sidewalls as additional surface that does not transmit force to the ground, but allows for higher coefficient of friction in total. Regards etc.,

Wojtek

---
WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

Col wrote:

If driving off road on sand or soft ground would you not need a wider tyre rather than a narrower one to increase the footprint of the tyre to give it more traction and stop it sinking into the sand etc. Although deflating the tyres slightly I imagine would have a similar effect.
Cheers
Col

No, counter-intuitively, as TheWojtek pointed out, a narrower & taller tyre will almost always outperform a wide & shorter one, especially on sand.

You might think that the wider contact patch when deflating has to do with the width, but it's actually the elongation of the tyre itself that spreads the weight over a bigger surface (not sure if I'm explaining this well).

When it comes to rock, you actually don't want too much sidewall bulge, as this increases the chances of a cut, and a longer tread 'catches' the next rock while you're still on the 'current' one.

edit: this photo explains it better than I can

 --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport Supercharged V8 HSE Dynamic



Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

A picture is worth a thousand words! RRS HSE Dynamic SDV6 2014

Nemo mortalium omnibus horus sapit

this chap fitted 275/55 KO2s, no rubbing.

https://www.facebook.com/groups/7845373949...391093553/ --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport Supercharged V8 HSE Dynamic



Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

Naks is right, contact patch is measured in length not width. the more you air down, the greater your lenghwise contact patch. side-wise makes sense if you think about it, but is factually not correct.

No way (in my opinion) would 285/65 R20 (879mm dia) fit. Max 275/55 R20 (811mm dia) - just!. But I have a RRS MY 2010 so could be completely incorrect.