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Wheel and tire upgrade advise - 19x9.5 & 19x10.5

Robbo70

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Hi , sorry if this has been done to death.... I have read so many posts but cant get a definitive answer to my specific W&T combo..
I have some BC Forged wheels that I had refurbished and powder coated, so like new again and under 10kg / 22lbs each.

Rim Sizes
F 19 x 9.5" offset +35
R 19 x 10.5" offset +50

Tires being considered -
Conti Sport Contact 6 ( offered a cheap deal)
F 275/35/19
R 295/35/19

concern is ( according to Tire Size Calculator ) I will lose;
Front Vs OEM ( 255/40/19) ~5mm side wall & -1.5% overall diameter
Rear Vs OEM ( 275/40/19) ~5mm side wall & -2.2% overall diameter

I'm already lowered on shockworks coilovers maybe 2"/50mm, so this new set up will be wider but not higher and will sit out/poke more with the offset and rim width increase.

Do you see any fitment issues?
Will it look crap with less sidewall or not really noticeable being 5-7mm ?
Do you think i will need to raise it a bit ? was scraping with a Borla centre muffler, now replaced with X- Pipe and currently ok.

Also looked at F 285/35/19 & R 305/35/19 but very limited and expensive options here in AU, x3 the price if you can get them ! tire shop also said they are too wide for my rims ( which i doubt)

IMG_4311.webp
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MAGS1

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Continental makes the Extreme Contact Sport02 in 305/35/19 if you want to go that route. Not sure what availability and pricing on those looks like in AU. Otherwise, I’d say your tire sizes are just fine with the wheel width you have. 275/35 is a pretty thin sidewall, you’ll feel more of the road than you would with a taller sidewall. I personally don’t mind it but it’s not for everyone
 
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Robbo70

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Continental makes the Extreme Contact Sport02 in 305/35/19 if you want to go that route. Not sure what availability and pricing on those looks like in AU. Otherwise, I’d say your tire sizes are just fine with the wheel width you have. 275/35 is a pretty thin sidewall, you’ll feel more of the road than you would with a taller sidewall. I personally don’t mind it but it’s not for everyone
no sign of the Conti ECS02 unfortunately, we are often 2years behind on new rubber.
yeah lose 5-6mm of sidewall on the 35profile option , think I will physically measure them before I commit to fitting as actual measurements can vary between brands
 
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Robbo70

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So this is how a 275/35 Conti looks next to a 255/40.. way too small !

IMG_1179.webp
 

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Robbo70

Robbo70

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I have found this website handy over the years.

https://tiresize.com/calculator/
Yep I’m a regular on there !
I find a few discrepancies tho,
Eg if you look at the difference in diameter in this calculation ,704-688=16mm, so the sidewall difference should be half ie 8mm yet the calculation shows 109-104=5mm
So something not right going on there .

IMG_1176.webp
 

MAGS1

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Yep I’m a regular on there !
I find a few discrepancies tho,
Eg if you look at the difference in diameter in this calculation ,704-688=16mm, so the sidewall difference should be half ie 8mm yet the calculation shows 109-104=5mm
So something not right going on there .

IMG_1176.webp
Sidewall height is a % of the tire width, so to get the sidewall height, multiply the width of the tire by the aspect ratio (in this case 295x.35)
 
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Robbo70

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So got this all sorted now
ended up with -
275/40/19 ( OEM size from the rear moved to the front.)
Rear are now 295/40/19, have plenty of sidewall "meat".. car sits a little higher but thats ok as i was scraping on some speedhumps/driveways anyway
IMG_4400.webp
.

IMG_4399.webp


IMG_4402.webp


IMG_4398.webp
 

Robottrainer

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Hi , sorry if this has been done to death.... I have read so many posts but cant get a definitive answer to my specific W&T combo..
I have some BC Forged wheels that I had refurbished and powder coated, so like new again and under 10kg / 22lbs each.

Rim Sizes
F 19 x 9.5" offset +35
R 19 x 10.5" offset +50

Tires being considered -
Conti Sport Contact 6 ( offered a cheap deal)
F 275/35/19
R 295/35/19

concern is ( according to Tire Size Calculator ) I will lose;
Front Vs OEM ( 255/40/19) ~5mm side wall & -1.5% overall diameter
Rear Vs OEM ( 275/40/19) ~5mm side wall & -2.2% overall diameter

I'm already lowered on shockworks coilovers maybe 2"/50mm, so this new set up will be wider but not higher and will sit out/poke more with the offset and rim width increase.

Do you see any fitment issues?
Will it look crap with less sidewall or not really noticeable being 5-7mm ?
Do you think i will need to raise it a bit ? was scraping with a Borla centre muffler, now replaced with X- Pipe and currently ok.

Also looked at F 285/35/19 & R 305/35/19 but very limited and expensive options here in AU, x3 the price if you can get them ! tire shop also said they are too wide for my rims ( which i doubt)

IMG_4311.webp
That's exactly what I'm doing. Ive done the rears. Fronts are next
 

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Robbo70

Robbo70

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That's exactly what I'm doing. Ive done the rears. Fronts are next
have a look at my photo above, 275/35/19 has a very small sidewall and is a small tyre overall.. i didn't get it as it looked "odd" and was going to reduce my ride height and ride comfort too much..
I ended up with Front 275/40/19 ( OEM rear size) and Rear 295/40/19

IMG_4471.webp


IMG_4399.webp
 

Robottrainer

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Mine is lowered 1" so the shorter side well suites it. Plus the shorter side wall makes for a stiffer tire for better handling but yes the ride will suffer a bit.
 

BlueHPP

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One suggestion is to apply PPF or use fender spats to protect the side of your Mustang. When m car was new It caught a few rock chips on the side. You can get self apply PPF at Anchor Room or spats from CJ POny parts.
1768279305455-tp.webp
 

Robottrainer

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One suggestion is to apply PPF or use fender spats to protect the side of your Mustang. When m car was new It caught a few rock chips on the side. You can get self apply PPF at Anchor Room or spats from CJ POny parts.
1768279305455-tp.webp
Right behind the door gets it too. Lower section just in front of the back wheel
 

BlueHPP

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Yep, with the wider tires and the +35 offset the side of the car will see some rocks. Factory 19 X 9.5 for the HPP/HP is +40 and 265/40/19. I put on PPF between the front wheel well and the back wheel well which helped greatly but still had some chips. The front fender spats stopped almost all of the impacts ( in conjunction with the factory rocker extensions). Still would recommend PPF in front of the rear wheel well.
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