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305/30/19 Square on 2019 Bullitt

1,170
1,145
In the V6L
I'd like to run 305 30 19s square on my Bullitt Mustang. I've searched forum here and have been on a number of different sites seeking information. I've also been to a couple of tire stores and spoken to Tire Rack as well and I'm still not comfortable with what I'm being told.

I want to run this setup WITHOUT spacers on 19 X 11 wheels. The information that missing is what the ET needs to be front and rear.

I'm running Steeda suspension parts including dual rate springs which lower the car 0.5" from stock.

Is anyone running a similar setup on their S550 Mustang?

TIA for all help and information.
It's amazing that you've had a lot of responses, but nobody has explained the problem you're facing. It's simple. The S550 wheel wells are big enough for big tires, but the rear stub-axle sticks 1-1/4" (32mm) further into the rear wheel well than the front stub axle sticks into the front wheel well. That means, to center the tires up properly, you need a 32mm difference in offset. The rear tire/rim has to be set 32mm further inwards than the front. That's why the GT350 rims are 11" rear ET62 and 10.5" front ET 30 - a 32 mm difference.

Now, if you run a square set of 10" ET37 rims, the inner flange at the front will be the right distance from the strut and the outer flange at the rear will be the right distance from the outer fender liner. No spacers required with that spec. Those 10" rims would easily take 285/35 tires, like the Goodyear 3R or a Toyo R888R. You'd get great great performance and you wouldn't need spacers. But 305's on 11's won't work. At ET37, 11" fronts would hit the strut and 11" rears would hit the fender.
 
249
272
Exp. Type
HPDE
Exp. Level
20+ Years
NC
I've got a 2019 Bullitt running long studs, 25mm spacers, 19x11 wheels, and about -2.8* camber. If your is a magneride car, you can't use the pre-installed hub if you do go longer front suds. I saw someone posted Apex wheels link to their setup which allows for staggered offset wheels, but won't allow easy rotation.
 
33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
I've got a 2019 Bullitt running long studs, 25mm spacers, 19x11 wheels, and about -2.8* camber. If your is a magneride car, you can't use the pre-installed hub if you do go longer front suds. I saw someone posted Apex wheels link to their setup which allows for staggered offset wheels, but won't allow easy rotation.
Thank you. Yes, my car is equipped with magneride. Why won't the longer studs work with a magneride suspension?

I appreciate the information.
 
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33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
It's amazing that you've had a lot of responses, but nobody has explained the problem you're facing. It's simple. The S550 wheel wells are big enough for big tires, but the rear stub-axle sticks 1-1/4" (32mm) further into the rear wheel well than the front stub axle sticks into the front wheel well. That means, to center the tires up properly, you need a 32mm difference in offset. The rear tire/rim has to be set 32mm further inwards than the front. That's why the GT350 rims are 11" rear ET62 and 10.5" front ET 30 - a 32 mm difference.

Now, if you run a square set of 10" ET37 rims, the inner flange at the front will be the right distance from the strut and the outer flange at the rear will be the right distance from the outer fender liner. No spacers required with that spec. Those 10" rims would easily take 285/35 tires, like the Goodyear 3R or a Toyo R888R. You'd get great great performance and you wouldn't need spacers. But 305's on 11's won't work. At ET37, 11" fronts would hit the strut and 11" rears would hit the fender.
JAJ, thank you for the information!! Makes sense to me.

If I understand correctly you're suggesting I run 19 X 10 X ET37 square with the 285/35 tires.
 
1,170
1,145
In the V6L
Thank you. I saw on another forum your comment about how the magneride hubs are different than a non-magneride car. Did you resolve that situation and if so, what solution did you find?
I'm not sure I understand your question - I don't have a problem with hubs or studs. I have a GT350 and my track setup is GT350R front hubs (that mount with four bolts and come with nearly 4" long studs) so I can run GT350 aluminum rear wheels in 19x11 ET 62 all around using 35mm spacers at the front. When I want to run the regular ET30 19x10.5" front wheels without having the ends of the long studs exposed, it takes about 45 minutes to slide the calipers out of the way and remove the rotors so I can unbolt the R hubs and re-install the non-R hubs the car came with. Simple. I don't know if swapping hubs back and forth is as easy on a Mustang GT. I think the Magneride-equipped GT's also use a four-bolt front hub, but I've never worked on one so I'm not sure if it's as easy to swap hubs as it is on the GT350.
 
33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
I'm not sure I understand your question - I don't have a problem with hubs or studs. I have a GT350 and my track setup is GT350R front hubs (that mount with four bolts and come with nearly 4" long studs) so I can run GT350 aluminum rear wheels in 19x11 ET 62 all around using 35mm spacers at the front. When I want to run the regular ET30 19x10.5" front wheels without having the ends of the long studs exposed, it takes about 45 minutes to slide the calipers out of the way and remove the rotors so I can unbolt the R hubs and re-install the non-R hubs the car came with. Simple. I don't know if swapping hubs back and forth is as easy on a Mustang GT. I think the Magneride-equipped GT's also use a four-bolt front hub, but I've never worked on one so I'm not sure if it's as easy to swap hubs as it is on the GT350.
Oh, I thought you had a GT.

Thanks for your comments. Much appreciated.
 
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249
272
Exp. Type
HPDE
Exp. Level
20+ Years
NC
I think you misunderstood my previous post. Apex makes a 19x11 set up you can run without spacers. However, the wheels are not rotatable front to rear. you could swap them side to side if running a non-directional tire. The MR equipped GT/Bullitt have the same four bolt hub as GT350. If you look through my build thread, you will see them. Probably not as easy to remove and install as the non-MR cars single large bolt. Thought I'd save you the search.
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As JAJ said, you can run 19x10 wheels all day with 285's. But if you have to run spacers anyway, why not go the 19x11 route with 305's?
 
33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
I think you misunderstood my previous post. Apex makes a 19x11 set up you can run without spacers. However, the wheels are not rotatable front to rear. you could swap them side to side if running a non-directional tire. The MR equipped GT/Bullitt have the same four bolt hub as GT350. If you look through my build thread, you will see them. Probably not as easy to remove and install as the non-MR cars single large bolt. Thought I'd save you the search.
View attachment 66419
View attachment 66420
View attachment 66421
View attachment 66422
As JAJ said, you can run 19x10 wheels all day with 285's. But if you have to run spacers anyway, why not go the 19x11 route with 305's?
 
33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
Thank you. This clarifies the issue of the hubs and running extended studs. I agree about running spacers and 305s so . . . I'll likely go that route. If I remember correctly the wheels need to be 19 X 11 X ET52, right?
 
33
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Libertyville, il
I don't want to run spacers on the track so I went with Apex SM-10 ET26 front / ET52 rear waiting for them to arrive.
I looked at that package, too. I decided to run Flow One Race Spec F2 in Gloss Black ET52. I'll buy Ford Hubs - HUB395 - that have extended studs and 25mm spacers. This solution is more cost effective for me than the APEX package as the wheels are on sale for $225 on close out at Tire Rack. I'll get tires in the spring.

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225
176
Exp. Type
Time Attack
Exp. Level
Under 3 Years
Bulgaria
I looked at that package, too. I decided to run Flow One Race Spec F2 in Gloss Black ET52. I'll buy Ford Hubs - HUB395 - that have extended studs and 25mm spacers. This solution is more cost effective for me than the APEX package as the wheels are on sale for $225 on close out at Tire Rack. I'll get tires in the spring.
This looks like a great package for the price. I get the benefit of square wheels but just can't make myself run spacers. Hope you enjoy your new setup. I will also get tires next spring as I have a set of 275/35/19 that I still in his first 1/3 of heat cycles so it will work great to finish off the season with it.
 

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