MCS 17" to 15" rims. Experiences needed.

[MarkPe]

Am after peoples experiences who are currently driving an MCS on 15" rims but originally started on 17" rims.

What kind of differences can one expect to notice with regards to the following:
- Acceleration
- Handling, corning, ride comfort.
- Braking

I am currently considering changing my 17" S Spokes for some 15x7 rims with some 205/55/15 tyres. The current list consists of
- Team Dynamics Pro Race 1.2
- Team Dynamics Pro Race 2
- OZ Ultra Legerra

This should reduce my wheel weight by almost 50%, which is quite a saving.

Any other thoughts and opinions welcome.

[ALD0]

Hello,

My personal expirience is:

Better acceleration
Worse Handling/Cornering
Better ride comfort
Didn't really notice any diff in brakes tbh, you should also get better fuel economy.

Hope that helps

Si

[MarkPe]

Thanks for your comments Si.

[minicore]

I would agree with Si, and add that the biggest issue is a cosmetic one - I wouldn't swap my 17s for 15s, regardless of the slight performance increases. In fact, I'm considering putting 18s on.

But in summary, you could expect better acceleration and ride, but worse handling... in my experience at least.

[Mike_in_Berlin]

You're better half is less likely to scratch your alloys if you have the higher profile tyres...

Might be important!

[MarkPe]

Speaking from experience there Mike (think I remember reading something in another thread about that)

Ok so the handling is worse but improvements in the other areas.

Any body out there that was happy with this kind of change?

[PM_]

IMHO 16" is a better compromise

[Humourl3ss]

I've run 15, 16 and 17 inch rims. The 15s are for (non-RF) snow tires, so my experience is biased somewhat in that they lacked ultimate grip and were noiser. Offsetting that is the plusher ride and a slightly more lively feel (down likely to reduced weight and narrower 195-series rubber). 17s were on the dreaded S-spokes, and thus had a clunky, crashy, ponderous sensation; albeit one tempered by greater grip. They also look cartoonishly, freakishly large to me (though I'm old enough to remember when a Porsche 911 came standard with 15" wheels).

As others have said, 16" rims and rubber are probably the best compromise.

[MarkPe]

Thanks PM_ and Humourl3ss, interesting to hear you would both go for 16" rims.

The idea for going for the 205 tyres is to at least give the same width as my current 17x7, so hopefully not comprising the grip to much.

[Alan Wolfe]

I use 15 x 6.5 inch wheels (Flik Blast) for autocross and track days. I don't know where the handling comments come from, but my data says much better handling with the 15 inch wheels. Mostly due to 10 lbs less of unsprung wheight at each corner.

Big wheels are all about bling, unless they facilitate big brakes.

Alan

[MarkPe]

Interesting Alan, can I ask what data you are refering too?

As I currently dont have big brakes that wont be an issue.

[F355GTS]

I'm a bit confused by the suggestion of better acceleration, 15" with 205/55 is a larger o/a rolling radius than 17" with I assume std 205/40's therefore acceleration will be marginally impaired, I appreciate we are talking negligable amounts!.

I've no doubt ride comfort will be improved

[SalemMINIDriver]

We go back and forth between R12s with 175/65 R15 and R85s with 205/45 R17 RF summer tires. I don't recall the weight difference, but I've added it up in the past, and the rolling mass reduction is substantial. I notice no difference in acceleration and very little difference, if any, in ride comfort. The only positives in downsizing from my experience are lighter steering and reduced tramlining. They are outweighed by the reduced grip and less crisp handling on turn-in that accompany the skinnier tires. Keep your expectations modest. You're setting yourself up for disapointment if you anticipate the car being transformed.