Time for new wheels & tires - 15" vs 16"

[glarsenov]

Hello guys!

after reading tons of messages and checking a lot of pictures I still can't decide in which direction to pull the trigger on a new set of wheels and tires for my car.
Currently, I'm on stock wheels, suspension, and 205/40/R17 Michelin Pilot Sport 4 tires.

I'm very satisfied with their performance but it's time to change them and here comes my dilemma.
I'm getting old and it starts bothering me the harsh driving dynamics of the suspension on this little car.
I would prefer a more cushioned driving experience on broken road surfaces which are plentiful in my country(Bulgaria).
I use my car only during summer on road trips and spiritual driving from time to time during the weekends. I do not do track days whatsoever.

What I'll like:
- checking the "meaty tires thread" here in the forum I do like the tires to have a bit more thickness, it gives me that racecar vibe.
- to be quiet on a highway
- UHP summer tires for good grip and performance


What I won't like:
- not sure whether 15" with 205/50 tires won't look too small in the wheel wells
- if overall diameter is too small, maybe the speed difference on 6th gear on a highway will be noticeable, making the car run at higher rpm for the same 130km/~80mph (based on the speed limit here)
- rubbing of any kind
- losing a lot of driving dynamics while pushing the car in corners

Rims:
15"
TD Pro Race 1.2 15x7 ET35 - 170$ per piece - 680$ in total
OZ Superturismo 15x7 ET42 CB63.4 - 180$ per piece - 720$ in total
OZ Ultraleggera 15x7 ET42 CB75 - 200$ per piece - 800$ in total

16"
TD Pro Race 1.2 - doesn't offer them in that size
OZ Superturismo 16x7 ET42 CB63.4 - 191$ per piece - 764$ in total
OZ Ultraleggera 16x7 ET42 CB75- 233$ per piece - 932$ in total
As seen the prices of any setup is pretty similar, so I won't count on that while making the choice.

As for the colors:
TD is gloss black
OZ Ultraleggera: Matte black
OZ Superturismo: Grigio Corsa

==================================
Tires
205/50/15:
- TOYO Proxes R 888-R
- TOYO Proxes TR1
- YOKOHAMA Advan-Fleva (V701)
- YOKOHAMA AD08RS
- NANKANG Sportnex NS-2R

205/50/16 (as for this size I read that some people do rub here and there)
- CONTINENTAL PremiumContact 6
- YOKOHAMA AD08RS
- YOKOHAMA Advan Fleva (V701)
- GOOD YEAR EFFIGRIP PERF
- FIRESTONE ROADHAWK 2


205/45/16 or 215/45/16
- CONTINENTAL UltraContact
- CONTINENTAL PremiumContact 6
- YOKOHAMA AD08RS
- YOKOHAMA Advan-Fleva (V701)
- NANKANG Sportnex NS-2R

So far I would go for 16" inch wheels in 205/50/R16 and either AD08RS or Advan Fleva or any of the CONTIs, but I'm not sure whether I won't hit issues such as rubbing or being too noisy on a highway.
To me this option, it's like the best of both worlds as cushioned driving and good-looking size of the rims.
Bu then in another moment I think that 15" wheels with the same 205/50 tires could be better. Lighter wheel + tires and no rubbing based on experience here

I would highly appreciate any input on the topic and if you have any pictures of any of those setups that would be absolutely amazing.
Thank you in advance,
Georgi

 

[Stubborn Approach]

Look at the overall diameter of any tire you buy, the 205/50 will likely be the same diameter as the 17” tire you have now so the wheel gap will remain the same.

Folks recommend more sidewall for more comfort so pick whatever wheel size you think is best. I have 15, 16 & 17” wheels and they all feel the same to me as far as ride quality goes, but the lighter the wheel & tire setup, the better the Fiesta drives. Aim for <35lbs per wheel/tire imo.

 

[glarsenov]

Checking on some tire calculators it appears that there is a bit of difference i between stock 205/40/R17 and 205/50/r16. The 16" are definitely bigger.

When I use 205/45/R16 the size is almost the same and maybe this setup will be the closest to stock, but then I lose that bit of cushion in between 45 and 50.
Looking into 15" they appear smaller .

 

[dhminer]

On stock suspension you shouldn’t have much of a problem going up slightly in size to the 205/50R16. Lots of folks with stock wheels go to 205/45R17.

I’m on 215/45R16 now and didn’t notice a ton of difference in the ride quality just by downsizing tires. Still just as harsh, but in theory less likely to dent a wheel from potholes which was a win in my book. The big change in ride quality came from swapping out the stock suspension for BC coilovers. WAY better ride on the street and adjustable for track use. Not saying you should swap to coils, just saying you shouldn’t expect a wheel and tire change to make the ride much better. Managing expectations and all that.

I’d just pick what you like the look of and has the best tire options.

Here’s a photo but keep in mind my car is quite low on the coilovers so don’t expect similar wheel gap. 16x8 Konig Dekagrams powder coated with 215/45R16 Falken 615k+

 

[Stubborn Approach]

View attachment 65286
Checking on some tire calculators it appears that there is a bit of difference i between stock 205/40/R17 and 205/50/r16. The 16" are definitely bigger.
View attachment 65287
When I use 205/45/R16 the size is almost the same and maybe this setup will be the closest to stock, but then I lose that bit of cushion in between 45 and 50.
Looking into 15" they appear smaller .
View attachment 65288

A tire calculator has no basis in reality. Look up the specs of the actual tires you are looking to buy. Every manufacturer uses a different method to size their tires and only the actual specs matter.
Example: 205/50/15 R888R = 23.1” overall diameter
205/45/16 NS2R = 23” diameter

 

[Capri to ST]

If you get a significant lighter wheel/tire combo, you can soften up the ride some even if you stay on 17-in wheels. That's because there's less weight banging up and down.
I have 17-in wheels in stock size, but they are 5 lb lighter per wheel than the stock wheels, and it has made a noticeable difference. Smaller diameter tires are not necessarily lighter because they have taller sidewalls if you want to closely approximate the original overall diameter.