One thing is important to understand since there's a popular misunderstanding: It isn't
the tire itself supporting the car's weight. It's the air in it which carries the weight. That's
why you see the tire flat without the air in it. So the tire's job is mainly to hold the air in
it and the tire's structure is mainly stressed by tensile loading, not by compressive load.
not so much at least and excluded the tread of course. So after you apprehend this it's
easy to understand the rest. Lower profile tires got less air, so the load carrying needs
to be accomodated by using higher air pressures and reinforcing the tire structure. If
the tire's stucture is stiffer it's likely heavier too. I'd usually skip XL type tires if possible.
Sadly I can't. On my Mini I'm running 205/45 R17 in the summer, only XL available (88Y).
Winter tires are 195/55 R16 91H, again XL. While some SL would have been available, I
wanted Michelin and H rated tires (210 m/h) and that sadly mandated LI 91/XL. On my
GTI I'm running 225/40 R18 92Y in the summer season, again XL. I think it makes sense
and this car is heavier compared to the Mini and 92Y is common for this car even though
Michelin offers an 88Y version of the PSS. In the winter season I'm running 225/45 R17
94W, so again XL. It's similar to the Mini's winter tires - Michelin make the W rated in a
94/XL version only and I didn't want to content myself with V (240 km/h) during the cold
half of the year. I know, it's kind of a first world problem. Well, my old Porsche fortunately
is running 205/55ZR16 91Y and 225/50ZR16 92Y - both are SL.
However, as a bottom line, the biggest issue for me is, many sizes aren't even available as
SL. I'm forced to run XL tires on two of my cars even though I'd prefer to run SL tires or I
had to make a compromise in other regards (speed rating).
comfy seats + soft suspension + high profile, perhaps this is too much.
going a little faster into corners even with this small engine, it felt really understeering. i had to lift the foot.
i hope low profile will decrease jelly effect
Grip doesn't depend on the tire size alone. It's the type of tire more than the size. And
it's (the lack of) sufficient fron camber on very most commuter cars. I'd bet there's less
than one degree of negative camber. Increasing front camber to -1° will increase lateral
grip and reduce understeer. Without appropriate camber any further effort is worthless.
Btw, understeering isn't necessarily a bad thing. It's designed into your car to save your
life. As a matter of fact the majority of drivers isn't trained to cope with oversteering.
rubber height about same with 205/50 17
The vast majority of tire choice in that size is XL (LI 93) with the Pirelli Cinturato P7 summer
tire (Euro spec, not NA spec AS) in 205/50 R17 89V being one of the few exceptions. That
said I would expect very little gain in going from 205/55 R16 to 205/50 R17 particularly as
tire choice is quite limited compared to the very common 205/55 R16.
Honestly, you'll hardly ever make a good handling car out of your Citroen C3. At least it's
quite comfortable for such a small car.
If you actually want to improve handling I'd do a search for DS3 Racing components fitting
your C3. See what I said about front camber above.
If your stock size is 205/55 R16 (91) I wouldn't even bother with XL/94 tyres, but just fit a set
of Michelin Pilot Sport PS4 instead. These are sitting on the front axle of my Porsche and are
MUCH better handling than a vanilla Eco/Touring tire that's likely fitted from factory. Michelin
even make a 94Y version of it if you feel better with going for an XL tire.
Start from there - with an appropriate tire.
.
