Speaking of old brochures reminded me of my exploring the Toyota Corolla specs as a future "possible". The "base" version (a bit of a misnomer as it's very well equipped) comes on 16s, the mid-range on 17s and the GR Sport** on 18s,but they all have exactly the same suspension set up, so the latter is for looks only.

**Not to be confused with the GR Corolla which is going to be produced at Burnaston and rumours persist that it may even be sold here. 

https://www.toyota.com/grcorolla/

5 hours ago, Botus said:

16" wheels won't make it a wobbly mess.

for most of the time it will be a bit brittle and ride a bit stiff just like all modern cars do, but come a bend, the front will wash wide, the steering will be disgusting and vague.  And overall the car will be slower, less responsive and less fun to drive

 

ooh heck , thats a pessimistic prognosis. Hoped for a smoother quieter ride not brittle & stiff one but definitely wouldnt want to trade that for what you seem to suggest a skating rink on bends. I have ,in last week ,driven 2 titaniums 19plate with 16" with 205.60.r16 and didnt experience what you refer to .... heres hoping i dont !

38 minutes ago, cee1bee said:

heres hoping i dont !

We'll know on Tuesday so looking forward to your comments. This is an area where we all have different views, driving styles and priorities. From what you've said, I suspect you'll be fine.

 

ok,  been several days with new wheel / tyre combo. Acceleration and fast corners have no perceptable difference. Unfortunately , the tyres michelin primacy 4 mo ( which are made for mercedes with their personal compound )  seem to show quieter on the graph mode on my recorder app on my phone , but somehow both my wife & I "think" it sounds louder on old style tarmac. On new style "silent" grade tarmac they are probably just as quiet.  eeek lot of money nor little on no return !!!

 

13 hours ago, cee1bee said:

michelin primacy 4 mo ( which are made for mercedes with their personal compound )

Not clear why you ended up with a Merc specific compound?

Your other issue was ride - any change there?

1 hour ago, Eric Bloodaxe said:

Not clear why you ended up with a Merc specific compound?

Your other issue was ride - any change there?

michelin primacy were 68db as a "noise generator" that i know are measured from outside , but that noise also is next to the occupants.  primacy 5 were higher db . primacy 4's that are mainly left were ones tha merc approved and also marketed as good for electric vehicles ( presume cos ev makers have no significant noise other than tarmac noise !

bumps seem bit more deadened , duller less intense and graph supports that. other than that not sure what u query with "ride"

2 hours ago, cee1bee said:

merc approved and also marketed as good for electric vehicles

Meaning they have stronger sidewalls to deal with the extra weight and torque of the EV.

3 minutes ago, unofix said:

Meaning they have stronger side walls to deal with the extra weight and torque of the EV.

oh hell , so not for silence  BUT may be even louder ? !! and less forgiving on bumps ? !!!    

5 hours ago, cee1bee said:

bumps seem bit more deadened , duller less intense and graph supports that. other than that not sure what u query with "ride"

As above - you complained of "bumps" which it seems have reduced only slightly, perhaps not surprising with stiff sidewalls.

was on phone for ages to michelin tech , stated my ideal is a tyre that has least tarmac road roar & softer on bumps.  he said being ev rated tyre would make it quieter hmmmm 

what do people think is a known or great likelyhood of being soft on bumps & quiet on tarmac

 

58 minutes ago, cee1bee said:

he said being ev rated tyre would make it quieter

Why would he think that ?

Tyres for EV's are no different to tyres for other vehicles when it comes to noise. Some tyres will be quieter and some will be louder, the fact that they are recommended for EV use does not guarantee a quieter tyre.

What you should be looking at is the actual rated sound level. It is very important to understand that a change of 3dB will either double or half the sound level compared against another tyre.

Using for example of a tyre rated at 71dB.

A tyre with a sound level of 68dB will be half as loud compared to the 71dB tyre.

Similarly a tyre with a sound level of 74dB will be twice as loud compared to the 71dB tyre.

MO was a designator long before any electric car came out

quite a lot of vehicles used fractionally customised iterations of a std tyre - often where the engineers found strange peculiarities with the way a car behaved in certain circumstances during development - where they were unable to mask it via traditional engineering and car design, they ask tyre manufacturers to make it go away 

then every tom ***** or harry bolts on budget tyres r us and the car is never quite the same

I would not anticipate a significant gain going to the non MO variant of the same tyre - MO likely pushes the characteristics closer to one made by continental 

 

the EV tyre debate here is interesting

electric cars are heavy as hell and have massive instantaneous torque - so I would expect it to have incredibly stiff sidewalls - then to eek out a longer range they are narrow for low wind resistance, don't deform wasting energy on ride comfort, have low rolling resistance, I thought from a tyre compound that usually generates no grip at all - all of which I would expect makes for a noisy tyre ?

4 hours ago, Botus said:

the EV tyre debate here is interesting

electric cars are heavy as hell and have massive instantaneous torque - so I would expect it to have incredibly stiff sidewalls - then to eek out a longer range they are narrow for low wind resistance, don't deform wasting energy on ride comfort, have low rolling resistance, I thought from a tyre compound that usually generates no grip at all - all of which I would expect makes for a noisy tyre ?

Agree !

EV's make a lot of 'engine' noise.  It's just at a pitch that most people can't hear.  This is the issue with the dB system.  I've recently bought a fridge with a much lower dB rating than the old one, but it's at a more irritating pitch and feels more intrusive.  I never found the tyre noise ratings to make any difference in the real world, but I am very sensitive to noise (on one side anyway!).  I certainly wouldn't pay out again to replace all the tyres in the hope of less noise...

55 minutes ago, TomsFocus said:

I certainly wouldn't pay out again to replace all the tyres in the hope of less noise...

I'm pretty sure many of these issues are simply down to road surface. The Fiesta ST for example is never going to ride like a limo (wouldn't expect it to!) but on a stretch of smooth tarmac road, with a good substructure, it's fine.

Problem nowadays is that sort of road is as rare as hens teeth, and in my area even A roads have been "surface dressed" with tar and chippings and done poorly at that. If you do manage to hit a stretch of proper road after a spell of that, it's as if you flicked an "off" switch!

Noise is an incredibly subjective thing. There's a long thread on another forum where some people claim their STs are virtually inaudible, others have sold them because they couldn't stand the noise any longer! Yet they're all the same car, mostly on the same tyres (Michelin PS4).

1 hour ago, TomsFocus said:

EV's make a lot of 'engine' noise.  It's

I'm out walking a lot, and on roadside stretches I find the tyre noise from EVs sounds just as loud as ICE cars.

3 minutes ago, Eric Bloodaxe said:

Noise is an incredibly subjective thing. There's a long thread on another forum where some people claim their STs are virtually inaudible, others have sold them because they couldn't stand the noise any longer! Yet they're all the same car, mostly on the same tyres (Michelin PS4).

Indeed.  There are plenty of reviews suggesting my new fridge is 'silent'.  Yet it's doing my head in from 15ft away even through a closed door.  

dBa is an industry scam to allow them to make irritating loud noise, disturbing people in their homes - but the meter reads a fake happy clappy result 

Quote

There is some debate relating to the accuracy of the A-weighted system's accuracy compared to human hearing and in complex noises. Regardless, many years of observational data have confirmed its usefulness for environmental noise and predicting hearing damage

Typical noise levels

• 20 dBA: whisper, quiet room
• 30 dBA: soft music
• 40 dBA: home computer fan
• 50 dBA: home air conditioning, light outside traffic
• 60 dBA: normal conversation
• 70 dBA: flushing toilet, home dishwasher, noisy room, most cars at 70mph
• 80 dBA: server room, alarm clock, inside an airplane
• 85 dBA: accepted level of hearing damage over time
• 90 dBA: lawnmower, hair dryer, blender
• 100 dBA: construction site, riding a motorcycle
• 110 dBA: rock concert, jackhammer
• 135 dBA: air raid siren
• 140 dBA: jet engine, pain threshold, serious hearing damage possible 
• 150 dBA: handgun
• 180 dBA: rocket launch

i heard a titanium with conti eco contact 6 ( or 3) prob 2019 vintage that was so quiet and bang free , but then it cant be traced anbymore grrrr

so maybe stuck with a 68db primacy 4 mo

im told that 500-1000  miles of use may settle it to a queter ride ?