285/35 vs 275/35 rears on MY08 DB9

[danieldenham]

Hi

I'm looking at options for Michelin Super Sports on the rear of my my08 DB9 with 15 spoke 19" rims. Firstly, I have been known to curb an alloy so a bit more rubber might help but also I think the rear rim/arch could do with a bit more filling. I've read a few people commenting (sub other PH threads) on the 285/35 fitments driving exactly the same as the 275 but I thought I'd start a specific tread to check.

My maths say that the increase in width gives a 3.5mm increase in diameter which I can't see affecting the speedo enough for worry.

Has anyone got any experience and comment?

Daniel



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[danieldenham]

mikey k said:

I used this calculator on my alloys when I upsized to my Michelin PSS's

http://www.1010tires.com/Tools/Tire-Size-Calculato...

Thanks, it says 1.04% too fast! which is fine.

Does anyone have any experience to say if the ride is affected? The load rating of the tyre does go from 100y on 275 to 104y on the 285 MPSSPorts. In theory, this extra load capacity may make the ride firmer but has anyone had actual experience?

Dan



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[danieldenham]

simonpa said:

I've just done this, but went from standard Bridgestones to the 'oversize' version of Kumho Ecsta.

Great info, thanks.

Anyone else with 'oversized' experience?

Dan



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[danieldenham]

Speculatore said:

..... Getting them on-line from 'Tyreleader'.

Thank you for the recommendation.

I ordered four (2x245 & 2x285) Michelin Pilot Super Sports from Tyreleader for £738 delivery!

They arrived perfectly 4 days later as predicted.

Fitting them on Wednesday.

Will feed back.

Daniel



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