Tire Size Questions - new here!

[vpec13]

I just picked up a 2015 GT with the PP. Have the 19 inch wheels. I believe 245 up front and the 275/40/19 in the back I believe. I went through a few pages here and google but didn't really find a concrete answer. As far as rear tire size goes on the factory wheel, how big can you go? What is optimal. I've seen posts about 305's in the back, but people suggesting 275 (factory) in the rears. Just looking for thoughts, experiences, recomendations. I'm not new to modding cars, but new to modding mustangs.

Thanks again!

V

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[JackImpact]

Pretty sure its 255 front, I can run out and check my car in a sec if needed. I am also interested in this.

 

[vpec13]

Pretty sure its 255 front, I can run out and check my car in a sec if needed. I am also interested in this.

You're right 255 in the fronts. Fat finger problems.

 

[BlownGP]

The rear wheels are only 9.5" wide.

Can you run a 305 tire? Yeah.
Should you. Probably not. I doubt you would gain much traction.
285 would be the max IMO.

 

[vpec13]

The rear wheels are only 9.5" wide.

Can you run a 305 tire? Yeah.
Should you. Probably not. I doubt you would gain much traction.
285 would be the max IMO.

So most just stick with the 275?

 

[Monopoly]

I've seen many posting 285s on pp rear rims. Sidewall height is 35 instead of 40? Cant remember.

I'll be needing new tires soon. Honestly going with the best price/quality tire and match between 275 or 285. Since our cars are staggered sizes some tire shops may have inventory for one size and not the other I'm finding.

 

[vpec13]

I've seen many posting 285s on pp rear rims. Sidewall height is 35 instead of 40? Cant remember.

I'll be needing new tires soon. Honestly going with the best price/quality tire and match between 275 or 285. Since our cars are staggered sizes some tire shops may have inventory for one size and not the other I'm finding.

I'm strictly a Tire Rack guy as I can't find anywhere to beat their prices. But yeah i've seen mixed answers. I'm curious if going to a 285 would really make any benefits or not.

 

[ugstang17]

If you have modded cars in the past then you would be aware that power at the wheel is a large factor in tire selection. What's the power at the wheel currently? What's the application, street, corner carving or straight line traction? Roll traction or Standing traction? Seeking best overall 4 season traction or best tire for summer traction or best track traction? Better 411 generates better feedback.

 

[vpec13]

If you have modded cars in the past then you would be aware that power at the wheel is a large factor in tire selection. What's the power at the wheel currently? What's the application, street, corner carving or straight line traction? Roll traction or Standing traction? Seeking best overall 4 season traction or best tire for summer traction or best track traction? Better 411 generates better feedback.

Currently it only has a Corsa Cat-Back. My goals for the vehicle would basically be just bolt-on's and a tune, lower it. This being my first V8 with this much power traction/handling is somewhat important for me. This is my daily driver, I live in NJ, when it snows I can work remotely. So probably looking for more a summer/performance tire to get me great traction with some good tread life as well.

 

[ugstang17]

Currently it only has a Corsa Cat-Back. My goals for the vehicle would basically be just bolt-on's and a tune, lower it. This being my first V8 with this much power traction/handling is somewhat important for me. This is my daily driver, I live in NJ, when it snows I can work remotely. So probably looking for more a summer/performance tire to get me great traction with some good tread life as well.

Welcome first to having an engine that runs on all 8...just a joke between me and my boss at work who drives a Miata. I always tell him there is an issue with his car because it only hits on 4 cylinders.

So we now understand you seek summer traction. What is your target HP number at the wheel? What gear will you be running or what gear are you currently on if you plan to stick with that? Will it see a track? If so road course or quarter mile? Makes a difference on the setup.

BTW - Traction with good tread life is virtually an oxymoron. With traction comes a sacrifice in tread life.

 

[vpec13]

Welcome first to having an engine that runs on all 8...just a joke between me and my boss at work who drives a Miata. I always tell him there is an issue with his car because it only hits on 4 cylinders.

So we now understand you seek summer traction. What is your target HP number at the wheel? What gear will you be running or what gear are you currently on if you plan to stick with that? Will it see a track? If so road course or quarter mile? Makes a difference on the setup.

BTW - Traction with good tread life is virtually an oxymoron. With traction comes a sacrifice in tread life.

I haven't thought about HP numbers yet. I have the PP package so that's the gearing i'll be sticking with. As I mentioned previously, just going to be a daily to and from work, won't be tracked or road coursed or anything.

 

[ugstang17]

So. no E85, no gear change. Assume PP1 has a 3.73 since I don't memorize option package features. Daily driven, no issue with snow. Stock suspension I assume. So you can rule out the exotic Toyo's and other track performance series tires. The tire sizes from the factory are a decent selection for staright line traction given the options you wish to do with the car. A 285-35-19 series on the back will add a little width and .2" height giving you more contact patch while staying very close to being speedo accurate. The next question since I don't have PP1 package on mine is the factory rim width and if you seek a different rim setup. IF staying stock then the 275 that is on the car will be optimal. When you start to squeeze a larger tire on a given rim the tire will become more rounded at the same operating tire pressure. So you lose contact patch. And as the tire heats up while driving (theory of kinetic energy vs friction can't be avoided) the gas in the tire (air of N2) will expand respectively as ALL elements do in the presence of rising temps. You would need a 10" rear rim to run a 285 and gain the benefits of its size IMHO. If the PPQ rear rim is a 10" then you are there. If not that is somethign to contemplate.

If staying with stock wheel setup, spend a little more and look at the Michelin Pilot 4S or save a few bucks and run the Continental Extremecontact Sport. You could also consider a NItto 555G2 with the given setup and future you wish to take the car, but not certain Tire Rack offers Nitto. I currently run the Nitto G2 on my setup and with the additional HP the tires are seeing over the previous setup (630 vice 545) I am looking to upgrade as well. On the previous setup at 545RWHP from a role at 50mph they would spin slightly and then go. Granted I could blow them off at a street light, as compared to the R series Mickey Thompson 275/60/15 Pro's I ran on at the track, but you won't get that traction from a street tire and get any mileage.


So after all my rambling 275 or 285 in a 35 series on a 19. And 285 if the rear is 10" or if you choose to upgrade rims and go with a 19x10. As for brand Nitto G2 will do okay. Research indicates that the Firestone Firehawk 500 is doing a good job at your HP level as well if not a tad better than the Nitto 555G2. Continental is another option and maybe a bit better than the previous two. Then all out would be the Michelin Pilot 4S if money is no object. If I were in your shoes I would run the 275 series Michelin 4S or save a few bucks and if the rim size is a 10" width step up to the 285-35-19 on the rear (leave fronts alone) and do the Continental Extremes for about 200 less than the 275 Mich 4S setup.

Good luck.

 

[vpec13]

So. no E85, no gear change. Assume PP1 has a 3.73 since I don't memorize option package features. Daily driven, no issue with snow. Stock suspension I assume. So you can rule out the exotic Toyo's and other track performance series tires. The tire sizes from the factory are a decent selection for staright line traction given the options you wish to do with the car. A 285-35-19 series on the back will add a little width and .2" height giving you more contact patch while staying very close to being speedo accurate. The next question since I don't have PP1 package on mine is the factory rim width and if you seek a different rim setup. IF staying stock then the 275 that is on the car will be optimal. When you start to squeeze a larger tire on a given rim the tire will become more rounded at the same operating tire pressure. So you lose contact patch. And as the tire heats up while driving (theory of kinetic energy vs friction can't be avoided) the gas in the tire (air of N2) will expand respectively as ALL elements do in the presence of rising temps. You would need a 10" rear rim to run a 285 and gain the benefits of its size IMHO. If the PPQ rear rim is a 10" then you are there. If not that is somethign to contemplate.

If staying with stock wheel setup, spend a little more and look at the Michelin Pilot 4S or save a few bucks and run the Continental Extremecontact Sport. You could also consider a NItto 555G2 with the given setup and future you wish to take the car, but not certain Tire Rack offers Nitto. I currently run the Nitto G2 on my setup and with the additional HP the tires are seeing over the previous setup (630 vice 545) I am looking to upgrade as well. On the previous setup at 545RWHP from a role at 50mph they would spin slightly and then go. Granted I could blow them off at a street light, as compared to the R series Mickey Thompson 275/60/15 Pro's I ran on at the track, but you won't get that traction from a street tire and get any mileage.


So after all my rambling 275 or 285 in a 35 series on a 19. And 285 if the rear is 10" or if you choose to upgrade rims and go with a 19x10. As for brand Nitto G2 will do okay. Research indicates that the Firestone Firehawk 500 is doing a good job at your HP level as well if not a tad better than the Nitto 555G2. Continental is another option and maybe a bit better than the previous two. Then all out would be the Michelin Pilot 4S if money is no object. If I were in your shoes I would run the 275 series Michelin 4S or save a few bucks and if the rim size is a 10" width step up to the 285-35-19 on the rear (leave fronts alone) and do the Continental Extremes for about 200 less than the 275 Mich 4S setup.

Good luck.

Thanks for the nice write up man! I'm pretty sure it's a 9.5 Inch rear width rim. But I think I will stick with the 275/40/19 and get the Continentals. That's what I'm gearing for.

 

[ugstang17]

Thanks for the nice write up man! I'm pretty sure it's a 9.5 Inch rear width rim. But I think I will stick with the 275/40/19 and get the Continentals. That's what I'm gearing for.

No problem. You always get better thought out suggestion when you provide as much 411 as possible.

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