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GT350 & GT500 Maximum Track Wheel Fitments

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50Deep

Jockin' GT350's
837
835
Sacramento
A good hallmark of any company is thinking ahead and preparing itself for the next iteration of performance. At the same time, recognizing the models that laid the foundation. This is what brings Signature Wheel into preparing some maximum fitments for the ongoing GT350/R, as well as the upcoming GT500.

Over the last few years I have been through 8-10 sets of wheels on my own GT350 and GT350R. Each set came at a personal cost of a few grand, but the ability to test wheel, tire, and offset combinations on my own car was important. Also partnering with track focused entities like the Ford Performance Racing School to put products to the test. Fully understanding and being able to explain what will and will not work on these cars is what I believe sets us apart from other companies. Through that process I have a gained a better understanding of what these platforms want, both on track and the street.

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It has been established that the 950A Carbon Package production will be limited, and there will be many GT500’s with aluminum wheels having a smaller footprint for traction. We are aiming to fulfill the needs of those owners with rim selections that can allow you to maximize grip on track, as well as offer street or track setups for those ordering carbon wheel cars. If any of you have seen the front offsets of the GT500 we anticipate the sunken in look of the front wheels is going to leave many wanting more. Whether your desire is less weight, more caliper clearance, wheel rotation at all 4 corners, or a more aggressive stance we can oblige.

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The GT350 and GT500 will have many similarities in terms of suspension geometry and philosophy when it comes to track performance, meaning many of the lessons learned from the GT350 will carryover. The newer GT500 brake system is really going to change the game as the car will come with a 20” wheel standard, and 19” wheel fitment unlikely to be an option. With a bridge design similar to the GT350 caliper we would also anticipate many aftermarket 20” options causing caliper/barrel damage as seen on the GT350 as well. This is what brings me to introduce our new maximum fitments for the GT350 and GT500.

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50Deep

Jockin' GT350's
837
835
Sacramento
On the GT350 we have had great success with the 19x11.5 square setup on track. This fitment allows you to run a 315/30/19 Pilot Sport Cup 2 at all 4 corners and rotate the wheels/tires side to side. We also have recommendations for a great street tire. As a street or track setup this will give you plenty of the grip you need.

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Street testing for the 20x11.5 square setup for the GT500/GT350 has gone extremely well. This setup allows you to run a 325/25/20 square on the street with no rubbing, scrubbing, or modifications. We also have several other street/track tire options depending on the look you want, road conditions, or sidewall needs.

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I cannot wait to take care of those first lucky owners that bring a GT500 our way. Our ability to custom build each set of fully forged wheels for street, track, or drag strip needs will continue on. Weights for the monoblock 19” - 20” setups fall between 20-26 lbs depending on the offset, width, and wheel design. I would be remiss for not mentioning that 19x12 and 20x12 rear fitments are also available for those drag strip lovers. However, they have not yet been tested for that environment, and generally push the limits of inboard/outer fender clearance under suspension compression conditions.

For those of you in the market for the GT500 we would love to hear what you project as being the best fitment on the car for your anticipated driving habits. Happy motoring!
 
How is the ride with the 20 series tires on the 20" wheels compared to the 30 series tires on the 19" wheels?
 

50Deep

Jockin' GT350's
837
835
Sacramento
How is the ride with the 20 series tires on the 20" wheels compared to the 30 series tires on the 19" wheels?
Car feels pretty solid with the setup. You can really tell there is extra rubber under you in those long sweepers. The 25 series setup felt similar to the 30 series, but Willow Springs such a bumpy track it’s hard to tell. I plan to run this setup at the track day in October and get some more feedback. Although the recommendation on the track setup for the 20x11.5 square would be a 315/30/20 square.
 
1,246
1,243
In the V6L
Looks like the FP specific GT500 CF Track Pack MPSC2's are up on TireRack now. 305/30x20 103Y and 315/30x20 104Y. Modestly priced at about $2k for a set of four. They don't spec the rim width range yet, but it'll probably be 11/11.5 like the GT350R. Spec sizes for GT500 base model are up as 295F/305R but it's not obvious which tire model it is yet.

*******UPDATE: The Michelinman.com website has a Ford Performance spec Pilot Sport 4S in 305/30x20 listed. This could be the GT500 non CFTP rear tire. *********
 
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Car feels pretty solid with the setup. You can really tell there is extra rubber under you in those long sweepers. The 25 series setup felt similar to the 30 series, but Willow Springs such a bumpy track it’s hard to tell. I plan to run this setup at the track day in October and get some more feedback. Although the recommendation on the track setup for the 20x11.5 square would be a 315/30/20 square.
How's the ride on those low profile tires on the street?
 

50Deep

Jockin' GT350's
837
835
Sacramento
Looks like the FP specific GT500 CF Track Pack MPSC2's are up on TireRack now. 305/30x20 103Y and 315/30x20 104Y. Modestly priced at about $2k for a set of four. They don't spec the rim width range yet, but it'll probably be 11/11.5 like the GT350R. Spec sizes for GT500 base model are up as 295F/305R but it's not obvious which tire model it is yet.

*******UPDATE: The Michelinman.com website has a Ford Performance spec Pilot Sport 4S in 305/30x20 listed. This could be the GT500 non CFTP rear tire. *********
Sweet find. I have been awaiting the information on the OEM spec for the wheels/tires. Seems like the GT350R spec will carry over
How's the ride on those low profile tires on the street?
I like it. Considering the R came with a 30 series it is a very similar experience. Even better without the tramlining and road noise.
 
1,246
1,243
In the V6L
I was given a copy of the Ford 2020 MAJOR PRODUCT CHANGES list for the GT350 and GT500 cars. Stock tire listed for the GT500 is Michelin Pilot Sport 4S on 20" rims. Doesn't specify sizes. GT500 CFTP is MPSC2 in 305F/315Rx30x20 on CF rims.
 

50Deep

Jockin' GT350's
837
835
Sacramento
I was given a copy of the Ford 2020 MAJOR PRODUCT CHANGES list for the GT350 and GT500 cars. Stock tire listed for the GT500 is Michelin Pilot Sport 4S on 20" rims. Doesn't specify sizes. GT500 CFTP is MPSC2 in 305F/315Rx30x20 on CF rims.

All indications are the car will maintain the same 20x11 / 20x11.5 as the R. Slightly different offsets appear to be in play though. Will be measuring a GT500 in real life here soon
 

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