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Discussion Starter #1
I'm about to buy some aftermarket 20'' alloys to replace my Audi 19'' segment ones which I'm not keen on.

For tyres the website recommends 255/30/20 but would 265/30/20 be better ?

Obviously I'd like the 255s as they're cheaper, but what do you reckon ?

Thanks
 

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What's the width of the new alloys?

OEM sizes are 265/30 or 275/30. This is on a 9" wide alloy.

Would go with 265/30 personally.
 

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im going to be running 245/30 on a 9.5. My old BBS CHs had 255/30 on a 9.5

Depends if your car is lowered and you need the clearance?
 

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I had 255 on a 9j OEM 20" segment alloy and it looked ever so slightly stretched to me.

I now run 275 on my 9j 20" rotors which have a slight bulge at the side so as Ben says, 265 would be the ideal.
Although not cheap as they're not as common as 255 or 275.
265 will allow you to inflate correct Audi pressures as well as its their standard for 20" alloys on the A5 :)
 

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If Audi send out a 9j rim with 275 then you can be pretty sure its fine to run ;) lol
 

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If Audi send out a 9j rim with 275 then you can be pretty sure its fine to run ;) lol

Oh I know mate, wasn't suggesting otherwise! It's quite noticeable having the extra width on the tyre to be honest but tyre pressures have been a pig to get right as they obviously didn't produce it for the Sportback!
Now I think I've got them right, the sidewalls are lovely and straight and fill the arches quite nicely for us people that haven't got lowered cars :)
 

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Oh I know mate, wasn't suggesting otherwise! It's quite noticeable having the extra width on the tyre to be honest but tyre pressures have been a pig to get right as they obviously didn't produce it for the Sportback!
Now I think I've got them right, the sidewalls are lovely and straight and fill the arches quite nicely for us people that haven't got lowered cars :)
Sorry mate, I wasn't insulting anything either lol. Just saying :)

I prefer a straight edge to my tyres much more than even the slightest hint of stretch which I had with the 255's and also with the 285's on the 10.5 but I don't think I could get away with anything wider? I might be able to and I was sure I could at one point but no Im not sure lol. 305's are what I would want so going above the "recommended max" there myself :) But might have to settle with 295's??
 

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Sorry mate, I wasn't insulting anything either lol. Just saying :)



I prefer a straight edge to my tyres much more than even the slightest hint of stretch which I had with the 255's and also with the 285's on the 10.5 but I don't think I could get away with anything wider? I might be able to and I was sure I could at one point but no Im not sure lol. 305's are what I would want so going above the "recommended max" there myself :) But might have to settle with 295's??

Did the 285 have a lot of stretch?
295 could be an option and 305 with your new suspension set up will give it a lovely arse if I do say so myself ;) but it's just the tolerances with the Quattro system :( one thing I do miss from my BMW days is having OEM staggered set ups!
 

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285 does have some stretch yes. See pic.

I don't think the tolerances would be an issue as you allowed something like 3 or 5% isn't it? But people do run staggered and I wont be so it should be ok??
 

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I think 295 on that would be a good look to be fair Ben ?

4% I believe the tolerance is? @DrEskimo knows as I've seen Lewis mention it somewhere before

Aren't you rear wheels wider than your fronts? Or did I read it wrong somewhere?
 

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No mate, 10.5 all round on that set up and 9 on the current.
 

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Ahh! I thought you had staggered set up, yeah should be fine then mate :)

A 295/30/20 tyre will give you a difference of 3.49% over stock 255/35/19.

If you reduced your tyre down to 295/25/20, that comes down to 0.83%...how compliant a 25 profile tyre is I have no idea! Awful I would imagine haha and they're over £200 a corner.
 

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Ahh! I thought you had staggered set up, yeah should be fine then mate :)

A 295/30/20 tyre will give you a difference of 3.49% over stock 255/35/19.

If you reduced your tyre down to 295/25/20, that comes down to 0.83%...how compliant a 25 profile tyre is I have no idea! Awful I would imagine haha and they're over £200 a corner.
The difference over stock is not the issue its the difference on the car between sizes.

And another point that is interesting is my speedo is more accurate now running 265/30/20 than ever before. Its now pretty accurate right up to the top end. It was indicating 30 and it does 30 and up the top end is close, I was hitting 167 iirc and that was actually 173 through the trap.
 

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The difference over stock is not the issue its the difference on the car between sizes.

And another point that is interesting is my speedo is more accurate now running 265/30/20 than ever before. Its now pretty accurate right up to the top end. It was indicating 30 and it does 30 and up the top end is close, I was hitting 167 iirc and that was actually 173 through the trap.
Yea I only know that the difference over stock can't be more than 2.5%. Whether this is true for a staggered set-up with regards to the tolerance for the quattro system, I don't know.

If the difference between the front and rear are so small thats its unlikely to cause an issue, will it really translate into any real world benefit...? Doesn't sound like its worth it to me?

Yea my A5 would do 67 when my speedo was at 70. Not sure if this is the same on my S5 but would imagine so. Guess making it more accurate is good for the speed runs/OCD, but its also nice knowing that if you go a little over the limit through a camera by accident, you have that 3mph buffer that will hopefully save you from a ticket!!
 

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The difference over stock is not the issue its the difference on the car between sizes.



And another point that is interesting is my speedo is more accurate now running 265/30/20 than ever before. Its now pretty accurate right up to the top end. It was indicating 30 and it does 30 and up the top end is close, I was hitting 167 iirc and that was actually 173 through the trap.

Sorry mate yeah you're right, I was just referring to stock as we know that's a platform to base things on

I haven't checked mine to be fair, think 275 makes mine under read slightly but I'd need to actually check.
Either way, I think you'll be fine with 295 tyres :)
 

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So in conclusion, 265 would be alot better than 255 ?

Not 'a lot' better, it would just be my preference as its a standard Audi size on the A5 and it makes getting tyre pressures easier.

It would be 'my' choice anyway :)
 

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Discussion Starter #20
Not 'a lot' better, it would just be my preference as its a standard Audi size on the A5 and it makes getting tyre pressures easier.

It would be 'my' choice anyway :)
So the main benefits are for tyre pressure ? What about rim protection as they're 10mm wider ?
 
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