[Jules59]

So after a fair bit of research I had Goodyear Eagle F1 Asymmetric 6 225/40R18 tyres fitted/balanced for £388. Had done 17800 miles on the OEM 205 tyres.
My initial assessment.
Upside: Saved lots of money - about £400. Personally I think the car looks better - the wheel/tyre combo fills the arches more, the tyres extend beyond the rim which looks much better than the "stretched" look of the OEM set up IMO. They should protect the wheels better (though bit late as the front rims are badly scuffed and due for replacement). Less road noise and slightly softer feel but that could be down to new thicker rubber. Less tendency to tramline or follow the camber. Less grabby / less torque steer on hard acceleration out of corners - not having to correct the steering as much - I have the LSD performance pack.
Downside: the speedo under reads by 2mph at an indicated 80mph and tyre doesn't look so skinny as sidewall is 8mm taller.
Overall an improvement I'd say - not sure why Ford used the 205/40R18 tyres which are stupidly expensive - they are actually the narrowest tyres you should fit to the OEM wheels.
FWIW I have no suspension modifications or mudflaps.

 

[mintmansam]

I suspect most manufacturers will use the narrowest possible to aid WLTP, wider tyres create more friction and aero drag, also in theory increase unsprung mass thus affecting NVH. In addition aqua-planning risk will increase with wider tyres.

Also the feel , playfulness of a car is generally different on narrower tyres. Most car in this segment are about fun, thus a bit of drama , wheelspin , lift off oversteer etc

Im not saying I agree with Ford or disagree with you, just answering why OEM go with the tyres they do

 

[Pistolpete]

I’m having 225/40/18 Dunlop Sport Maxx RT2’s all round fitted tomorrow. 205’s are just a complete rip off. No reason whatsoever for them to be the price they are, other than being ripped off, presumably because it’s what the manufacturer recommends.

 

[AMc]

It's supply and demand, there isn't that much of a demand for that size, so the manufacturing costs are more than those that are produced in larger numbers.

Same reason a little piece of Saffron rattling around in a glass jar requires a mortgage but you can buy a kilo of sugar for a quid.

 

[MarkEight]

Always been facisnated when someone will pay £THOUSANDS of pounds on a car, or maybe on finance, paying hundreds of pounds month in, month out, month in, month out, month in, month out, to never own the car.....yet then skimp on a couple of quid via buying non OEM tyre size tyres.

 

[Pistolpete]

Always been facisnated when someone will pay £THOUSANDS of pounds on a car, or maybe on finance, paying hundreds of pounds month in, month out, month in, month out, month in, month out, to never own the car.....yet then skimp on a couple of quid via buying non OEM tyre size tyres.

if the 205’s had of been the better option, I’d have gone for 205’s, but literally every person rates the 225’s over the 205’s.

 

[Jules59]

It's supply and demand, there isn't that much of a demand for that size, so the manufacturing costs are more than those that are produced in larger numbers.

Same reason a little piece of Saffron rattling around in a glass jar requires a mortgage but you can buy a kilo of sugar for a quid.

As a side note 1kg of sugar in Aldi was 65p last year now its 95p

 

[Jules59]

Always been facisnated when someone will pay £THOUSANDS of pounds on a car, or maybe on finance, paying hundreds of pounds month in, month out, month in, month out, month in, month out, to never own the car.....yet then skimp on a couple of quid via buying non OEM tyre size tyres.

You're making the assumption that the OEM tyre size is optimal - I'm sure many factors come into play during Ford's decision making.

The saving is a lot more than a "couple of quid" and I don't see it as skimping but rather an improvement. I've often improved my previous cars with remaps, suspension lowering, wider tyres, short shifters because the cars were better for it.

 

[Jules59]

What pressures do those with 225/40R18 tyres use ?

 

[ZoSo]

As the original super sports are 86 Y can l ask what the 225‘s are rated that everyone is fitting their mk8 with?

 

[Jules59]

All the ones I looked at were 92 Y

 

[ZoSo]

So that’s a stiffer side wall as higher rating and more than likely ,as wider,a heavier tyre so an increase in unsprung weight across 4 tyres.
Please correct me if l am wrong in my assumption.

 

[Pistolpete]

I’ve just Had 225’s fitted all round. Best decision I’ve ever made. Will never go back to 205’s. Ride is noticeably smoother. There will be a slight increase in unsprung mass, but it’s not noticeable. I highly doubt it would be to anyone tbh. I’m sure in the absolute extremes of driving and pushing the car to limits of grip, the 205’s may fair better, but for 99% of people and driving, I can’t see why anyone would choose 205 over 225.

 

[ZoSo]

I’ve just Had 225’s fitted all round. Best decision I’ve ever made. Will never go back to 205’s. Ride is noticeably smoother. There will be a slight increase in unsprung mass, but it’s not noticeable. I highly doubt it would be to anyone tbh. I’m sure in the absolute extremes of driving and pushing the car to limits of grip, the 205’s may fair better, but for 99% of people and driving, I can’t see why anyone would choose 205 over 225.

This is what concerns me most about changing from the OE pilot super sports.
They are superb in the dry especially in warmer conditions and l find them very predictable in the wet.
As to poor weather conditions then it’s a walk for me having experienced them in my first winter with the car (2019 to 2020) though l have been keeping an eye out for amother set of rims for winter tyres.
Whatever l fit be it either manufacturer and or size wise l feel l am not going to get the super sport level of grip and feedback.
My current feelings are PS 5 in the standard 205 40 18 86Y.

 

[MarkEight]

You're making the assumption that the OEM tyre size is optimal

I'm not making any 'assumption', I'm making an observation- when people are hungry to change tyre size, it is all so often that the 'alternative' one is also cheaper.
I'm not sure if that is just a stunningly amazing coincidence.

 

[mightbemeangreen]

It's supply and demand, there isn't that much of a demand for that size, so the manufacturing costs are more than those that are produced in larger numbers.

Same reason a little piece of Saffron rattling around in a glass jar requires a mortgage but you can buy a kilo of sugar for a quid.

Not really though is it ! Saffron is a hell of a lot harder to harvest than sugar is ! If high demand was to mean lower prices surely Gold would not be £50 an ounce but a hell of a lot lower ! some times high demand means high prices !

 

[ydnA]

Not really though is it ! Saffron is a hell of a lot harder to harvest than sugar is ! If high demand was to mean lower prices surely Gold would not be £50 an ounce but a hell of a lot lower ! some times high demand means high prices !

Gold and diamonds and the like intentionally have a low ‘supply’. There’s a lot of it around but it’s not sold in vast quantities in order to keep the prices high.

 

[AMc]

Not really though is it ! Saffron is a hell of a lot harder to harvest than sugar is ! If high demand was to mean lower prices surely Gold would not be £50 an ounce but a hell of a lot lower ! some times high demand means high prices !

And sometimes, low demand means high prices, as is the case for 205/40 performance tyres...

 

[Pistolpete]

I'm not making any 'assumption', I'm making an observation- when people are hungry to change tyre size, it is all so often that the 'alternative' one is also cheaper.
I'm not sure if that is just a stunningly amazing coincidence.

Huh? For me, price had absolutely nothing to do with it. The extra couple of hundred of quid for the 205’s is nothing. I went for the 225’s because of the positive feedback that so many people have provided. Best move I ever made. Only trade offs are a very slight decrease in MPG (barely noticeable and tbh, I don’t really care, it’s still great on fuel), and the car tramlines a bit more. That’s literally it.

 

[MarkP80]

if the 205’s had of been the better option, I’d have gone for 205’s, but literally every person rates the 225’s over the 205’s.

I'm not sure that it's possible to say "literally every person".
One confounding issue is that we need to remember that generally people are having new tyres fitted, so they're comparing worn out tyres of one size with brand new tyres in another. It's just not possible to "remember" what the original tyres were like when new.
Plus, you know which tyres you have fitted, so there is inevitably a level of unconscious bias when you've just shelled out £500, like it or not.
Some people's criteria for the 225 is that "they fit the arches better", a comment I've often seen, but not a criteria for everyone. You acknowledge yourself that you experience more tramlining with the 225.

The only real way to say which is "better" is a blind back to back test (to eliminate bias) with tyres with the same wear level, ie both sets new.
- and that of course is before we even talk about which brand of tyre. Is a Dunlop Sport Maxx "better" than a PS4 or PS5, or F1 Asymmetric 6 ? I would think it far more likely that you'd see bigger differences between brands than you would comparing 205 to 225.

For example, when you saw a huge improvement when you had the 225 Sport Maxx RT2 fitted, were you originally on 205 Sport Maxx RT2 or a different brand? (notwithstanding my comment about going from a worn out tyre to a new one).

I'm just suggesting it might not be a straightforward case of 225 being the better option.