Rivage tyre dimensions

Hi.

Iv currently got some 185/55/15 tyres on my 92 rivage which I believe was factory set. I am going to get all 4 alloys refurbed and renew the tyres.
I fancied going thinner on the side wall to 50 for a better look and wider to 195 to pertrude the rim of the alloy better which I'm reading alot of you have done and was a dealer spec.
Can anyone tell me and problems with this (other than speedometer possibly being out and steering being worse) such as lowering the car rubbing etc on these dimensions? I currently have -35mm eibach springs on standard shocks but will possibly be upgrading in the near future.

I'm looking into yokos/michelin/pirelli. Do not want to scrimp 😂👍

195 50 15 should be fine only 1.3% percent smaller than 185 55 15 so when speedo reads 90 mph you will be actually going 88.8 mph. also 195 50 15 is exactly the same radius as a 185 60 14, scrubbing depends more on the offset of the wheels

But the sidewall wont look noticeably thinner, you would need to go same width and 50 or 45 aspect ratio to achieve this. If going wider tyre then at the very least or should that be most a 195/45 tyre. Either of these options would lower the gearing.

Thanks for replying guys.
I'll be the first to admit I'm not great on my tyre or suspension knowledge.
Yes 50 will only be 5mm smaller than what I have on now but 45mm seems severe on a ride that is already very hard 😂😭
From the search iv done not read many on here running 45?.
What have you 2 got on? My rivage is totally standard with 15" le castellets what offset they are I'm not sure.
Cheers

this is 195 45 15 on 7x15 et 25 lowered 40 mm
or this is 195 50 15 on a 6x15 et 38 lowered 40mm

this is a handy site to compare tyre sizes
Tire Size Comparison

Thanks for your help 👍