255/50/20 is the standard tyre size in a supercharger infact it's the standard size on any 20" rim 275/45/20 is definitely non standard , not unheard of of course but most people leave standard . 2008 MY Supercharged
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axle wrote:

255/50/20 is the standard tyre size in a supercharger infact it's the standard size on any 20" rim 275/45/20 is definitely non standard , not unheard of of course but most people leave standard .

Have to say a while back i had 275x45x20's ….. never again had them on for about a Month … reverted back to normal 20's ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

What was the problem/issue Mick? I ask as they are a very close diameter....

hhhhhmmmm - and have ordered some "Winters" in that size.....

When i had them fitted i thought these should be ideal wider tyre better grip …. Wrong i got them when the weather was turning for the worse up here a while back and in the wet they just didn't hold the road at all , approaching bends in the wet made me slow down coz you got that feeling as if the car was about to start sliding …..

The grip on them as far as i was concerned was crap , but other people have had them on and not had any issue's with them …. thankfully i got them off before the snow landed … ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Well mine are full Winter Tyres with Softer compound so hopefully the will "Feel" and work OK.

Too late now so I will report on performance....

Diameter inches (mm) 29.74 (755.5) 30.04 (763) 0.3 (7.5) 1%
Width inches (mm) 10.83 (275) 10.04 (255) -0.79 (-20) -7.3%
Circum. inches (mm) 93.44 (2373.47) 94.37 (2397.04) 0.93 (23.56) 1%
Sidewall Height inches (mm) 4.87 (123.75) 5.02 (127.5) 0.15 (3.75) 3%
Revolutions per mile (km) 678.05 (421.32) 671.39 (417.1 -6.67 (-4.14) -1%

Speedometer Difference
Speedo Reading Actual Speed
20 mph (32.19 km/h) 20.2 mph (32.51 km/h)
25 mph (40.23 km/h) 25.25 mph (40.63 km/h)
30 mph (48.28 km/h) 30.3 mph (48.76 km/h)
35 mph (56.33 km/h) 35.35 mph (56.89 km/h)
40 mph (64.37 km/h) 40.4 mph (65.01 km/h)
45 mph (72.42 km/h) 45.45 mph (73.14 km/h)
50 mph (80.47 km/h) 50.5 mph (81.27 km/h)
55 mph (88.51 km/h) 55.55 mph (89.39 km/h)
60 mph (96.56 km/h) 60.6 mph (97.52 km/h)
65 mph (104.61 km/h) 65.65 mph (105.65 km/h)

Gazellio @ Prestige Cars wrote:

Too late now so I will report on performance ….

And what about rating the tyres …  ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Thats as well......

Whats the Rim width on the 10 Spoke 2011 Supercharged Wheels?

kingpleb wrote:

If you do get the tyres replaced and I still suspect they aren't the cause, ask to retain them as they could be used by another member, especially when they don't lead to the solution

Don't forget you need to be testing another car with the same size alloys and tyres on as the ride differs enough to notice between 18/19/20/22" rims

A new set of Pirelli Scorpion Zero is going on tomorrow morning.......so if anyone wants the current ( 255/50/20R) 2 yokohama advan 109 y ( on front ) and the 2 goodyear eagle rs-a (104v*), DO have them! Free and with my best wishes By all means I'll ask the tyre place to hold on to them for a week or so , pm me and then help yourself! I am in the SW 20 min. from Plymouth.

*NB something about the rear Goodyear Eagle's made the tyre place owner scratch his head in confusion. Apparently that specific model is not European ( something to do with the 104 v mark? ) and, according to him, may have come from some kind of US or foreign truck. No idea how accurate this notion is...but before someone trecks all the waydown here, I thought I'd mention it.

Testing another v8 RR with 20" rims tomorrow morning. I suppose if I love the ride on that one and STILL hate mine with the new set of tyres.....I.ll keep the tyres and swap cars. Gulp - this could turn into one expensive excercise. Never envisaged I couldn't love a Rangie, but I am just not clicking with the new one yet.

Incidentally...went to my local LR dealer today and one of their mechanics test drove the car. According to him, nothing wrong with the car's supension, exhaust, etc. Seemingly, a wallowey ride and sharp, jolty responses are normal for the supercharged. As is the occasional whine of the supercharger ( whereas I am used to the deep, melodic, rhythmic wooffle of the P38 and the Classic. Oh joy...

Just a quick point but the 104v tyres are under rated for the car, on 20" rims the load rating should be 109 minimum.

might have something to do with it? There is nothing that can't be fixed with a hammer😜😜
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northernmonkeyjones wrote:

Just a quick point but the 104v tyres are under rated for the car, on 20" rims the load rating should be 109 minimum.

might have something to do with it?

MPx wrote:

My guess is that it'll be a CO problem and you're going to find that out prettty quick...

If you get stuck and want a go in mine for comparison (albeit on the winter rubber for now)....I'm sure we could arrange a meet somewhere (East Devon?)

MPx.... If the new set of tyres won't yield the hoped for imorovement....I might just take you up on your kind offer. Cheers.

In the interest of full n'fair disclosure I must point out that there is a risk you'd never get your car back. Tonga green RR? Colour of my previous RR's and my favourite colour for a Rangie. Hunted high & low for one, couldn't get one. Which is why the new wobbly beast is Rimini Red. Meh, its alright....but I'd have a green one any day. Swap?