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I noticed that some members have put wider tyres on same rims
does this increase the height of the car and by how much?
Wont this ruin the handling though?
 

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I think the stock width is too narrow for the OEM wheels. I would like more tire, but like most on this forum, I would only go +10 and keep the same height ratio. So 205 fronts to 215 and 235 rears to 245. And IMHO I don't think it would ruin the handling, it would improve it. Now if you decide to go way wider, then you're going to have issues. How wide is too wide? I don't know. But I'll bet some of our clan will chime in with more info...
 

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215 and 245 are plenty to notice a difference. With more total rubber you get more dampening since there is more material to absorb impacts. It really stabilizes the whole car.

I think even wider tires really need wider wheels, but I think it's the point of diminishing returns to add even more mass to a nimble package.

Total grip isn't everything if you lose reflexes.
 

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I’ve kept to the same size but am about to change brands. The Michelins of the same nominated tyre size as the Pirellis are, like the Hankooks, actually wider than them and a little taller too.
 

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Going to wider tires like a 215/245 combo is fine and actually works better on the stock rims than the stock 205/235 combo. Note though that wider tires bring with them baggage. More drag, more rotating mass, more unsprung weight. Generally you get more for your efforts by going to a stickier tire rather than a much wider tire in the same compound as before.
Another issue is that 215 is the correct size on a 7" stock front rim but a 225 is over sized and not recommended. The rear is fine with 245 or even 255 but recommend staying with 245 in rear to avoid increasing understeer. This can somewhat be tuned if you have coil overs, different springs, etc. but with the stock setup you need to no go crazy or you could screw up the handling of the car.
If you change out to wider wheels you can go with wider tires but note my comments about that bad baggage in the first paragraph. Tire Rack has an excellent writeup about sizing tires for rim sizes.
Final comment....if you are changing tires sizes and compounds to lower lap times.....you should first learn how to use what you already have by attending an advanced drivers school. That will make more difference than all the mods you can throw at your car.
 

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Keep in mind same size tires vary slightly in (mm) from manufacturer to manufacturer (you have to visit each brand's website for specifics when getting down to millimeters of clearance concerns)
You want to see how tall a tire gets as you go wider, here is a Great visual tool I like to use where you can compare two different sizes simultaneously and get all the details from change in MPH to sidewall height and overall diameter and More......
 

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You need to get spring to make it even higher but keep in mind that if you will get bigger tires that it is with the recommended size my the model you have.
 

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I’ve kept to the same size but am about to change brands. The Michelins of the same nominated tyre size as the Pirellis are, like the Hankooks, actually wider than them and a little taller too.
Where did you get that info?
I just had a look at Tire Rack and it appears the diameter is the same F 24.5" Rear 25.5"

Am I missing something?

Pirelli (ARR)
Rectangle Font Parallel Pattern Number


Michelin front:
Rectangle Font Parallel Slope Pattern


Michelin Rear:
Rectangle Font Parallel Pattern Number

Rectangle Font Parallel Pattern Slope

It also looks as though the Michelins rears have a narrower tread, smaller tread depth, both F and R are heavier and they have a higher treadwear rating - meaning a harder compound (?). I know that this rating is not exactly comparable between tyres brands.
 

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Where did you get that info. I just had a look at Tire Rack and it appears the diameter is the same F 24.5" Rear 25.5"

Am I missing something?

Pirelli (ARR)
View attachment 124646

Michelin front:
View attachment 124647
Michelin Rear:
View attachment 124648
View attachment 124649
It also looks as though the Michelins rears have a narrower tread and have a higher treadwear rating - meaning a harder compound?
I should have qualified that. I thought everyone knows I run 17/18” tyres and I don’t go by what’s written in a table. Just standing the tyres side by side demonstrates the difference. Compare Pirelli P-Zero AR to Michelin Pilot Supersports 205/45x17 (F) and Cup 2 Connect 235/40x18 (R).
 

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I should have qualified that. I thought everyone knows I run 17/18” tyres and I don’t go by what’s written in a table. Just standing the tyres side by side demonstrates the difference.
Actually - I did know that - my bad.
 

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I'm 2 sizes up both front and rear. Went up 2 because of availability of PS4S at the time, but it's still a massive improvement over the Pirellis.

One thing I'd say, the taller and wider tyres actuslly help fill the arches MUCH better than previously, so at least aesthetically, it's great.

Might just but new wheels but I want @LLAGOS rims, they're just a bit expensive for me right now
 

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I'm 2 sizes up both front and rear. Went up 2 because of availability of PS4S at the time, but it's still a massive improvement over the Pirellis.
So, what size(s) are you at? What size wheels? Plus 2, so 225 fronts and 255 rears?
 

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I'm 2 sizes up both front and rear. Went up 2 because of availability of PS4S at the time, but it's still a massive improvement over the Pirellis.

One thing I'd say, the taller and wider tyres actuslly help fill the arches MUCH better than previously, so at least aesthetically, it's great.

Might just but new wheels but I want @LLAGOS rims, they're just a bit expensive for me right now
Seriously, you can't just drop that here without comments about what wheels/diameters you're running.

 

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Ummmm…. So I guess my tires are way oversized?
For a very spirited drive, the car feels perfect - like it’s on rails. The rubber is excellent on its own, so I think that’s the primary reason (as opposed to size).
But the front rubs a tiny bit when I turn the wheel to the max.
Bridgestone RE71R
265/35R19 98W
225/40R18 92W
This is how I bought the car from a 4C member that knows waaaay more than me about racing.
I may downsize to the plus 2 mentioned above for the next set of tires as the slight rub on max turning annoys me a bit.
 

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Ummmm…. So I guess my tires are way oversized?
For a very spirited drive, the car feels perfect - like it’s on rails. The rubber is excellent on its own, so I think that’s the primary reason (as opposed to size).
But the front rubs a tiny bit when I turn the wheel to the max.
Bridgestone RE71R
265/35R19 98W
225/40R18 92W
This is how I bought the car from a 4C member that knows waaaay more than me about racing.
I may downsize to the plus 2 mentioned above for the next set of tires as the slight rub on max turning annoys me a bit.
One assumes not on stock rims if you have 265 rears.
 

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On stock rims actually. The telephone dial rims. View attachment 124872

With respect, I wonder how much the previous owner really knew about racing.
Unless the stock wheels were widened (extra piece welded into the barrel), these tire sizes are way too wide. By increasing the width so much and maintaining the same aspect ratio, the tires are much taller (3/4” to 1”) than stock. Probably chosen for availability rather than function. No wonder you rub. But it also means unnecessary extra weight and rotational/unsprung mass. Fine if you are only after looks (well, except for the rub), but if this was his “racing” solution, well, I dunno. I think there are better solutions, all of which start with a wheel that is 1” wider, and has appropriate adjustments to offset.

BTW, your 225 fronts are “plus two”. 205 is stock. But by going “plus two” on your next set, you may want to decrease aspect ratio, or check tread with (the 215 is section width, which does not always correlate directly with tire tread width - it’s the treads that are likely rubbing the fender or liner). The rears are “plus 3” but still have the same aspect ratio as stock (35), which seems odd to me.
 
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