19x9 with 255/35r19 square setup

[Adidas_kn]

Has anybody done a rotateable square setup with the stock rear sized wheels and tires all around? Should improve handling too. Will the 255/35 and 9 wide clear up front?

 

[GetYourWheels]

with an aftermarket 19x9 wheel? Yes, depends on which one. Since not a lot of 19X9 options, I would default to the Forgestar wheels since they carry 19X9 in semi concave profile to work with the big brakes and give you a high enough offset so it doesn't stick out.

 

[Logic717]

with an aftermarket 19x9 wheel? Yes, depends on which one. Since not a lot of 19X9 options, I would default to the Forgestar wheels since they carry 19X9 in semi concave profile to work with the big brakes and give you a high enough offset so it doesn't stick out.

Got some examples?

 

[JDM_Man]

ARK 270 rims 19x9.5 +25 all around with 255/35/19 all around on Continental DWS 06's

 

[SKStinger]

ARK 270 rims 19x9.5 +25 all around with 255/35/19 all around on Continental DWS 06's

Yep. This is about as aggressive a setup you can run up front and it fits (there’s a thread with photos), so you’ll have no issues with a 19x9 square setup on the 255/35.

 

[POS VETT]

I recently acquired a set of Ford Mustang wheels (19x9 ET30). They came from a track-package car and had enough room to clear the Brembo calipers. The wheels have 255/40/19 tires and I know the tires are a bit larger. I have not had time for test-fitting, but maybe this weekend.

 

[Onno P]

Is it really gonna improve handling?
I guess you are going for Sport or Sport+ mode if ‘handling’ is an issue. The car already oversteeres because of the 80% going to the rear wheels. Widening the front tyres won’t overdo it then?

 

[POS VETT]

Is it really gonna improve handling?
I guess you are going for Sport or Sport+ mode if ‘handling’ is an issue. The car already oversteeres because of the 80% going to the rear wheels. Widening the front tyres won’t overdo it then?

There's a difference between on-power oversteer (also known as power slide) and oversteer with only maintenance-throttle or coasting like in a slalom or switchback situation. I assume you talked about on-power oversteer since you mentioned 80% torque to the rear tires.

A typical mass-produced passenger car in the market has a suspension calibration that leans toward understeer; negative camber and negative camber gain for the front are usually much less than the rear. Some of them have a characteristic of heavy understeer that using wider tires (than the rear) in the front only lessen the understeer. In the case of a Stinger with narrower front tires, using wider front tires (that matches the size of the rear) will definitely change the driving dynamics and for those who understand and seek a more-oversteer biased handling, it's a welcome change. For those who are considered an average driver, such dynamics might be a curse.

 

[CoconutRob]

I recently acquired a set of Ford Mustang wheels (19x9 ET30). They came from a track-package car and had enough room to clear the Brembo calipers. The wheels have 255/40/19 tires and I know the tires are a bit larger. I have not had time for test-fitting, but maybe this weekend.

I had a similar idea about the Mustang wheels but do you think the larger size will affect the all wheel drive system or the braking system?

 

[JDM_Man]

I had a similar idea about the Mustang wheels but do you think the larger size will affect the all wheel drive system or the braking system?

The rear already uses a 255/35/19 and if you go look at a tire size calculator you'll see that there is no rotational difference between a 225/40/19 (stock front) and a 255/35/19 which is why those sizes were picked originally. So in short a square 255/35/19 setup doesn't change anything for the AWD set up.

P. S you can also rotate tires lol.

 

[CoconutRob]

The rear already uses a 255/35/19 and if you go look at a tire size calculator you'll see that there is no rotational difference between a 225/40/19 (stock front) and a 255/35/19 which is why those sizes were picked originally. So in short a square 255/35/19 setup doesn't change anything for the AWD set up.

P. S you can also rotate tires lol.

The tires on a mustang I am referring to are 275 and 255 40-19

 

[MerlintheMad]

So many things to consider. The staggered set up gets 10K miles of Michelin summer tires. Then the last c. 5K miles I've been on Nitto Motivo UHP A/S tires, same staggered set up as the Michelins. Then I opt for a rear sway bar upgrade to make the rear feel more planted: and, I am told, also reduce oversteer. Sounds good to me! I do believe the understeer is less with the stiffer sway bar, even in "soft" setting. Now, I am told that I can put "rear" tires on the front if I choose (would require "rear" rims, though?); everything fits fine. But the oversteer would be back more noticeable with the wider front tires? Is that right? So then, would I put the Eibach rear sway bar on "stiff" to compensate for the wider front tires? The benefit is tire rotation for the first time; while handling should be about what it is now: with staggered set up, rear sway bar upgrade, improved stability in the rear and less oversteer. Am I thinking this through correctly?

 

[POS VETT]

So many things to consider. The staggered set up gets 10K miles of Michelin summer tires. Then the last c. 5K miles I've been on Nitto Motivo UHP A/S tires, same staggered set up as the Michelins. Then I opt for a rear sway bar upgrade to make the rear feel more planted: and, I am told, also reduce oversteer. Sounds good to me! I do believe the understeer is less with the stiffer sway bar, even in "soft" setting. Now, I am told that I can put "rear" tires on the front if I choose (would require "rear" rims, though?); everything fits fine. But the oversteer would be back more noticeable with the wider front tires? Is that right? So then, would I put the Eibach rear sway bar on "stiff" to compensate for the wider front tires? The benefit is tire rotation for the first time; while handling should be about what it is now: with staggered set up, rear sway bar upgrade, improved stability in the rear and less oversteer. Am I thinking this through correctly?

There are two or three things here.

Suspension first.
1. In some situations where handling is at its dynamic limits, the wider front tires will play their part providing more traction as in increasing oversteer tendency
2. The stiffer rear sway bar provides a quicker reaction of the rear suspension to reach its limit, meaning it increases the oversteer tendency

So, in a nutshell, with your scenario of using wider front tire and using stiffer setting on the rear b anti-sway bar will yield increased oversteer tendency.

Fitment.
I have never tried and fitted the OEM rear wheel and tire assembly up front. I read somewhere that it cannot be done as the tire hit the front strut housing. According to my calculation, the wheel backspacing for the front needs to stay less than 6.5 inches granted that the wheel is still wider overall than the tire.

Back to suspension. The suspension calibration has a very wide range when there are several variables to consider. In the case of my C6 Z06, the car has staggered tire sizes, but its alignment setting is aggressive enough to favor higher grip upfront (more negative camber, high caster angle, zero toe) yet the rear anti sway bar is set at 2 of 3 while the front is at full stiff (3 of 3). Its dynamic characteristic seems confusing at first but, when needed, it has copious amount of power to create an easy power slide while being not too twitchy at the limit. At one time, I experimented with full stiff for the rear anti-sway bar and a few bystanders could tell that "the rear is too stiff".

I would love to play with the suspension on the Stinger and, as usual, I would set the front to have more negative camber, zero toe, and as much caster as it can get. The rear would have minimal negative camber (negative half a degree) and slight toe in (half a degree to a degree). After all those, I would experiment with anti-sway bars and ride height to alter weight distribution.

 

[Adidas_kn]

I went with a square setup of 19x8.5 +33mm wheels with staggered factory tires. I will try to fit the rear 255/35 combo up front soon to see if they'll clear. The 225/40 are kinda stretched on the 8.5 wide wheels. Don't really like that look. I have noticed that the factory 26" OD tires cause the speedometer to read alot 1.2mph faster than its actually going compared to my phone GPS. Might have to go up to a 26.5 or 27" OD tire to correct this.

 

[POS VETT]

Speedometers in general are calibrated to read higher than actual speed to make you driving slower. The odometer should be accurate.

 

[Adidas_kn]

Speedometers in general are calibrated to read higher than actual speed to make you driving slower. The odometer should be accurate.

Yeah. I think you made that up.......

 

[JDM_Man]

Yeah. I think you made that up.......

It's on the internet, is has to be fact.

 

[POS VETT]

Yeah. I think you made that up.......

Do a search on it.

 

[mhal8876]

I went with a square setup of 19x8.5 +33mm wheels with staggered factory tires. I will try to fit the rear 255/35 combo up front soon to see if they'll clear. The 225/40 are kinda stretched on the 8.5 wide wheels. Don't really like that look. I have noticed that the factory 26" OD tires cause the speedometer to read alot 1.2mph faster than its actually going compared to my phone GPS. Might have to go up to a 26.5 or 27" OD tire to correct this.

The 255/35 tires will fit in the Front on the 19x8.5 wheels without issue. I ask the guy at getyourwheels and he answered all my questions regarding this same setup you got. And this is I'm gonna do on mine! Btw can you post a picture of your wheels? So we can see them.

 

[POS VETT]

I recently acquired a set of Ford Mustang wheels (19x9 ET30). They came from a track-package car and had enough room to clear the Brembo calipers. The wheels have 255/40/19 tires and I know the tires are a bit larger. I have not had time for test-fitting, but maybe this weekend.

The offset I posted above was incorrect. The correct offset is 42 mm.

The wheel clears the front Brembo caliper with plenty of space. The wheel DOES NOT clear the strut housing. A 3/8" (effective offset 32 mm) spacer solves the problem, but it needs extended-thread lug nuts (stock lug nuts engage only 3.5 turns with a spacer in place) with an extension that's less than 10 mm or it needs a spacer with lug holes large enough to clear the extension.

I believe I could get away with an 8-mm spacer and use the stock lug nuts (4ish turns)

As a reference, the OEM Stinger 19x8 front wheel has a 34-mm offset.

Here is a picture of the Mustang wheel.