Tyre fitment

Hello everyone,

After 2 years of absence I have returned to the RR ownership with a 1998 4.6 HSE

The immaculate 18 inch wheels are fitted with 285 55 18 Pirelli Scorpions.
These are really needing replaced and came across a nice set of 255 70 18.

Will these fit?

I must add that it has a spring conversion.

What's with the fancy name? I want a fancy name!

the_wolf said:

What's with the fancy name? I want a fancy name!

Click to expand...

Here you go

Ⓣⓗⓔ Ⓦⓞⓛⓕ

both sizes are wrong you need 255/55/18

wil2813 said:

both sizes are wrong you need 255/55/18

Click to expand...

I know they are not the right size, but my question is - will they fit without rubbing?

ⓡⓤⓓⓨ;3276567 said:

I know they are not the right size, but my question is - will they fit without rubbing?

Click to expand...

Your car would be illegal. 285/55/18 60 mph indicated 62.7 mph true. 255/70/18 60 mph indicated 66.2 mph true. 255/55/18 60 indicated 60 true.

Get a set of Nexen Rodians 255/55/18 60 from wil2813

Datatek said:

Get a set of Nexen Rodians 255/55/18 60 from wil2813

Click to expand...

Where are they advertised?

ⓡⓤⓓⓨ;3276649 said:

Where are they advertised?

Click to expand...

Just send wil2813 a PM.

wammers said:

Your car would be illegal. 285/55/18 60 mph indicated 62.7 mph true. 255/70/18 60 mph indicated 66.2 mph true. 255/55/18 60 indicated 60 true.

Click to expand...

Ah but the speedo is already inaccurate from factory
When mine wore 255/55/18 acording to my tom tom of the time when the speedo read 70mph I was at attualy doing 67mph! so a slightly bigger tire would bring it up to indicated speed
But physically yes they will fit

popcorn at the ready !!!!!

gfromleeds said:

Ah but the speedo is already inaccurate from factory
When mine wore 255/55/18 acording to my tom tom of the time when the speedo read 70mph I was at attualy doing 67mph! so a slightly bigger tire would bring it up to indicated speed
But physically yes they will fit

Click to expand...

That's quite accurate by some standards, my Xtrail was acually doing 38Kmh at an indicated 50
The OP should take into account that those tyres are not homologated for the P38 and may invalidate his insurance if not delared.

Agreed Datatek, but the currently fitted 285 55 18 will have the same result (insurance wise)

gfromleeds said:

Ah but the speedo is already inaccurate from factory
When mine wore 255/55/18 acording to my tom tom of the time when the speedo read 70mph I was at attualy doing 67mph! so a slightly bigger tire would bring it up to indicated speed
But physically yes they will fit

Click to expand...

It isn't a linear response. Usually they overread at low speeds and underread at high speeds. Inflexion point usually around 47 mph so the old duffers can get as big a queue as possible behind them.

gfromleeds said:

Ah but the speedo is already inaccurate from factory
When mine wore 255/55/18 acording to my tom tom of the time when the speedo read 70mph I was at attualy doing 67mph! so a slightly bigger tire would bring it up to indicated speed
But physically yes they will fit

Click to expand...

Your Tom Tom is only accurate on a dead flat road with no raise or fall in gradient.

Grrrrrr said:

It isn't a linear response. Usually they overread at low speeds and underread at high speeds. Inflexion point usually around 47 mph so the old duffers can get as big a queue as possible behind them.

Click to expand...

It is illegal for any vehicle manufactured in or after 2001 to be travelling faster than the speedometer indicates. Before that time the allowance was + or - 10% at 30 mph. That is why speed cameras are set not to flash until the speed limit +10% + 2 mph is exceeded.

wammers said:

Your Tom Tom is only accurate on a dead flat road with no raise or fall in gradient.

Click to expand...

Not so anymore since selective availability was turned off. I've been checking GPS speed against fixed sign indicators and average over flying kilometers, my tablet is withing 1Kmh. Of course it does depend on the quality of the GPS recever.

Datatek said:

That's quite accurate by some standards, my Xtrail was acually doing 38Kmh at an indicated 50
The OP should take into account that those tyres are not homologated for the P38 and may invalidate his insurance if not delared.

Click to expand...

my very first p38 I had years & years ago was ex Staffordshire motorway police & the clocks were branded "RS" which were very accurate, & back to tyres its right size or nothing imo

wil2813 said:

my very first p38 I had years & years ago was ex Staffordshire motorway police & the clocks were branded "RS" which were very accurate, & back to tyres its right size or nothing imo

Click to expand...

I have send you a PM Wil2813

Datatek said:

Not so anymore since selective availability was turned off. I've been checking GPS speed against fixed sign indicators and average over flying kilometers, my tablet is withing 1Kmh. Of course it does depend on the quality of the GPS recever.

Click to expand...

Yes point to point on a flat surface very good. GPS does not do up and down hills well. Don't think the average GPS would have the calculating power to work out the difference in distance up or down hills between two fixed points. Although they do read altitude above mean sea level. It's a lot further in distance travelled from the top to the bottom of an hill than the two fixed points would be on the flat. Having said that it would need to be a pretty steep hill to make a lot of difference.