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18 inch wheels that will fit the 15.5 inch brakes

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I'm leading the charge with these guys as well, is there any way you can fill out this form with the required info and post it so I may use it, since I do not have 15.5 brakes. Thanks

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VoodooBOSS said:
I'm a big fan of Apex but don't expect anything out of them. I've been working with them for almost two years to make a 18x10.5" wheel and nothing. We need 19x11 and 19x11.5" wheels and hell will freeze over before they have those sizes in fitment for our cars. Not likely their 18" wheels will fit over the larger calipers on the 15.5" rotors.

I contacted Apex as well. No new sizes until they clear existing inventory of Mustang 18s.
 
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Just got an e-mail back from Circle Racing...yayyyy

http://www.circleracing.com/

NO PROBLEM. WORKING ON NEW TOOLING TO ACCOMMODATE THE GIGANTIC BRAKES NOW. SHOULD BE ABLE TO MACHINE WHATEVER U WANT BY MARCH. CALL 559-251-1127 ASK FOR JEREMY AND GIVE HIM YOUR INFO AND IDEAS. THANKS
 

ArizonaBOSS

Because racecar.
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blacksheep-1 said:
I'm leading the charge with these guys as well, is there any way you can fill out this form with the required info and post it so I may use it, since I do not have 15.5 brakes. Thanks

tuJKDuol.jpg

ioFVu6pl.jpg

@Black Boss @cloud9 @StigsBaldBrother @mattlqx @fuhrius Any chance one of you gentlemen would want to get some measurements and then @blacksheep-1 can see what he can come up with? Click the link in the quote to go back to the original post just above w/ the required measurements.
 
I agree with Black Boss, I couldn't even get 19" wheels to clear the brakes. But, since I'll be taking the pads off this weekend, I'll see what I can do.
 

steveespo

Lord knows I'm a Voodoo Child
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Yes, Chicane23 is selling a wheel made by a company called MRR in 19x10/19x11 that is designed for the GT Performance pack cars, that wheel won't clear the GT 350 fronts!!!
No way an 18" wheel will fit over those monsters, the radial caliper mount on the bottom looks to be the tight point.
 
My estimated measurement of just over 8.875" radius for the caliper was a little low. Someone over on 6g has the caliper diameter at 17.9" from CAD, which would make the B dimension in the diagram 8.95".

Unfortunately, that closes the debate on any 18" wheels fitting. Not entirely surprised as the CCW's have a large barrel and weren't close.
 
I know it's not really relevant to the GT350 crowd since 18's won't clear the 15.5" fronts, but did anyone happen to check 18" clearance on the rear 15" GT350 brakes? I have a 2015 GT with Apex 18x11's which clear the 15" brembos in front, and I am hoping they might clear the GT350 rears also so I can upgrade!
 
@thatonenozz welcome to TMO. The clearance on the GT350 rear brakes isn't much more. Check in on the APEX 19x11 group buy thread and there is a photo of the clearance of the APEX 19x11 on the rear of a GT350. You might be able to determine if there's enough clearance and if not ask Ryan at APEX.
 
I have to ask, which model and size of tires does one hope to run on 18's for the GT350? We have had a few inquiries/requests for 18's on the GT350 so we're investigating.

We just acquired a '17 GT350 and have made a brake template. As others mentioned the rear caliper is just as ugly to fit as the front. Higher X factor but only slightly smaller OD. To fit an 18 over them will require a non ASTM conforming wheel. Rear drop center, stepped barrel and twisting the wheel over the lugs to install it. This is all in theory. Lots of engineering hoops to jump through and it would be just for the GT350 just so a handful of owners can save $40 a tire. As of now one can get the tasty 305/30/19 RS4 and RE71R for HPDE/track, AS autocross and 315/30/19, 325/30/19 Hoosiers. Cost is only a tad more than the equivalent 18's. I don't see any greater options in 305~325 width with diameters in the 26.3~27.0" sweet spot. As most of you know, the R's tires are about .6" shorter than the GT350. Same diff and trans so the gearing is a skosh lower and .3" lower effective ride height.

We're leaning towards just doing a specific set of 19's for the GT350. Those tools will also allow a C6Z/C7Z wheel
 
@949 Racing welcome to TMO. So far we have not found an 18" that will fit and that includes custom Forgeline and CCW wheels. You need to be careful with 19" wheels too as many either won't clear the calipers or clear but don't have enough clearance for track use. I have a set of the @APEXRaceParts 19x11" wheels on order and should be one of their first customers to receive a set and use on track. I'm going to use a 25mm spacer up front. Their wheels should have more brake clearance than the stock wheels.

Another expensive option is to install a Stoptech or AP Racing 15" brake kit so you can use 18" wheels. Look at the FR350S race car for guidance.

Tell us about your shop, you're in OC?
 
Us:

http://949racing.com/
http://supermiata.com/

We make wheels, among other things. We saw that the OEM 19 is already a bit unusual to clear the brakes. Parallel barrel, drop center at the very front. Ford uses the same casting tool for both and just adds a pad to the front. We'll do the same. Very little to be gained by doing two tools except a deep concavity on the fronts which would look goofy.

I just posted to see what tires folks are considering. From where I sit, 18's are an answer to a question that might not really matter. But I'm all ears.
 

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