[Mgs] A change to my SL500 - NMGC, NFC

[Dodd, Kelvin]

Max:

You do have a point. There is usually a trade off when going to + size
wheels unless you also go with exotic light weight (and delicate)
alloys.

If you check any of the serious ricky racer handling forums there are
discussions about the best combination of size and weight for a given
application.

On my daily driver, the recommended upgrade was only +1 from 14" to 15"
since the car was very sensitive to unsprung weight and rotational mass.
I went to +2 because used OE wheels from a different vehicle were
available in that size. I also chose to go up in tire diameter slightly.
Both choices reduced the acceleration of the vehicle, but the wheel
cost, improved cruising economy and cheaper tire size won out.

Getting back to MG content. Going to a +1 wheel will typically increase
unsprung weight and rotational mass, but it does give you a much better
choice of performance rubber which along with (IMHO) better looks.

Kelvin Dodd

> -----Original Message-----
> From: mgs-bounces+doddk=mossmotors.com at autox.team.net [mailto:mgs-
> bounces+doddk=mossmotors.com at autox.team.net] On Behalf Of Max Heim
> Sent: Tuesday, July 24, 2007 10:21 AM
> To: MG List
> Subject: Re: [Mgs] A change to my SL500 - NMGC, NFC
>
> That's a good point, But I don't think it's an issue with the
slim-spoked,
> forged wheels, so much as with the wildly-styled chrome rims you see
on
> Escalades and such.
>
> I remember when Vintage Motorsport did a tire comparison on a Volvo
sedan,
> the "plus 2" alloy wheel and tire combo outweighed the stock steel
rims
> and
> skinny tires by 31 lbs PER WHEEL! Tha's a lot of rotating unsprung
> weight...
>
> But, yes, when I see some really outrageous combo on a purported
> performance
> vehicle, I feel like asking them, "What weighs less: aluminum, rubber,
or
> air?".