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275/40-19's on the front. Smart or stupid?


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I'm in the home stretch of my SVTPP wheel and tire replacement and narrowing it down to the final few permutations of combinations to determine the one I'm ultimately going to go with. I'm sure the OE F-1 G: 2's are the bees knees at the track or in ideal conditions on well-kept roads, but I otherwise have very little confidence in them. I'd gladly trade-away some theoretical edge-of-envelope performance for a far better behaving everyday high performance V-rated (or better) all-season tire that will also extend the seasonal driving window - particularly with the ability to store away the OE wheels and tires for the track.


Tires that come close to the staggered OE step DO exist, but I opened-up the discussion to include the Ford Racing 19" SA19 wheels - just to expand the number of tire brands and sizes available. After all, if the telemetry isn't going to be spot-on (without a custom tune for that purpose), why hamstring myself by perpetuating the staggered setup (and the ridiculously-expensive OE replacement wheels)? I'm still waiting for Ford to explain how the 19 x 9.5" can be 4 x the price of either the 19 x 9" or 19 x 10". I'm not holding my breath either. I can come just as close to the OE rear wheel diameter with a 19" wheel and tire as a 20".


I've decided upon the Continental ExtremeContact DWS. I wasn't sure if I could trust how good the reviews seemed to be, but after replacing the summer-only Eagle F1 Supercar tires on my Taurus SHO with a set of 245/45-20 DWS, I'm absolutely hooked. I've never driven on a tire that seems to do everything so well without any one aspect coming at the expense of any other. They're incredibly silent and comfortable without seeming to give-up a bit of composure. Keeping almost 5,000 lbs of Taurus SHO in trim is no small feat. I even managed to be able to try them out in heavy snow (though the GT500 will never see any), and for as well as the DWS performs when conditions are clear, they're absolutely no worse on snow, ice and slush than a decent garden variety all-weather radial. Who could ask for more? Oh, and their profile and tread pattern are wicked. I'm absolutely hooked.


Although I hate to go to a narrower rear tire, the best I can do with a 19" wheel and the DWS is 275/40-19. The 1/2" difference isn't going to be earth shattering - and it's probably going to be offset in other ways by the taller sidewall and better inherent all-around hookup (than the OE F-1 G: 2's). One of the tremendous secondary benefits of a non-corner specific tire is the ability to rotate (at least) side to side. So I'm perfectly happy with that particular choice.


When it comes to the front tires, the OE size (for the SVTPP) is 265/40-19. The recommended snow tire size for all GT500's, and indeed the OE tire size for other Mustangs with 19" wheels are either 245/40-19 or 255/40-19 (with the Brembo). Sure, 265 takes things a little wider (and just a smidge taller), but in terms of overall clearance, I have very few concerns about the front accommodating the same 275/40-19's I will be using on the rear.


The advantages of a common tire size on all four corners is obvious - and huge. They're fully rotatable and every other benefit that becomes a limitation with corner-specific tires. The ONLY suboptimal factor from the perspective of the wheels and tires themselves is that 9.5" is the optimal wheel width - which are, of course, 4x the price of the 9" or 10" width wheels - the miserable sunzabitches. While I'm certainly planning to use a 10" wheel on the rear, my only concern about using a 9" wheel on the front is that it would tend to make an equivalent tire taller (though only nominally) - which is the opposite of the SVTPP's factory stance. (Although the baseline GT500's front wheel diameter is actually larger than its rear - 255/40-19 = 27.03 vs 285/35-19 = 26.85).


So, where I'm not quite decided is when it comes the effect a 275 front tire might have on handling. Yes, it's more surface area and a larger overall contact patch, but that also means lower relative pressure which could (at least theoretically) reduce handling in certain situations like hydroplaning in which narrower tires and higher relative pressure on the contact patch is better. With the OE 265 tires already being at the upper-limit of the stock front tire widths, am I pushing things too far by going to 275 (especially with a tire that's "A" rated for traction versus the F-1 G: 2's "AA" rating)? I know we're talking about fine tolerances here, but that's the point - particularly at 95mph.


And yes, narrower tire widths are available that would still allow me to rotate side to size - and if I were to use them, I'd almost certainly use the 9" wheel width with them. Setting aside for a moment handling properties, can anybody offer any insight into whether or not the 10" FR SA19 wheels would work leave sufficient clearance on the front of the car for the suspension mechanisms and so forth? I'd appreciate any insight anybody may be able to share.


To clarify the specific questions I'm trying to resolve, I'd appreciate any guidance about the following:


1. Would a 275 front tire (275/40-19) cause any clearance issues?


2. Would a wider (275) front tire improve handling? Could it also cause negative unintended consequences (i.e. reduced hyrdoplaning resistance)?


3. Is the 19 x 10" FR SVTPP clone wheel likely to retain sufficient clearance if used on for the front wheels too?


Thanks in advance for any relevant opinions or insight.

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