981 GT4/Spyder Wheel & Tire Fitment Guide

  • Updated

 

For 2014-2016 Porsche 981 Cayman and Boxster chassis 

View all 981 GT4 / Spyder Images

Vehicle Covered in this Guide
2016 Porsche 981 Cayman GT4 & Boxster Spyder

Rear Toe Link Clearance

Apex 19x11" rear wheels require the installation of aftermarket motorsport style rear toe links from companies such as Tarett, GMG, SP Motorsports, or BBi to achieve the clearance needed for the reduced wheel diameter. This will also allow you to correct your toe setting when dialing in more negative camber at the rear. 

Brake Clearance Information

In the engineering phase of wheel development we 3D scan factory brakes and review 2D aftermarket brake templates in order to optimize our barrel profiles and spoke curvatures. As a result, our wheels offer massive brake clearance so you can run the smallest possible wheel diameter.

* The factory yellow 6 piston 410mm PCCBs require 20" wheels for proper clearance. Read our article for more info.

Available Wheel Designs (click images to enlarge)

 

Forged Designs 

 Flow Formed Designs
 EC-7RS VS-5RS SM-10
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VS5RS1810ET25_Brushed_2K_01-500.png

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Bolt Pattern Center Bore Lug Seat Thread Pitch
5x130mm 71.6mm R14 Ball Seat M14x1.5mm

 

 

Performance Street & Track

Wider fitments for enhanced performance

Whether you enjoy modifying your GT4 for spirited street driving and canyon runs, or you are a hardcore track junkie chasing lap times, these wheel & tire configurations are best suited for enthusiasts looking for a dramatic improvement in performance and handling. These fitments incorporate wider 9” front wheels which provide superior tire sidewall support over the the factory 8.5" front wheels. A wider front wheel and tire combination will increase front end grip and close the stagger from front to rear resulting in sharper turn-in and less understeer. This is one of the easiest and most effective improvements you can make to your Porsche from a handling perspective. 

We've optimized the offset of our 9" front wheels to be a direct fit with 245 and 255 wide tires, and although some 265 wide front tires can work by maxing out camber to -1.9º by sliding the factory top hats all the way in, we recommend installing adjustable camber plates with a minimum of -2.5º for added fender clearance and improved handling.

If you plan to track your car, we highly recommended dialing in negative camber regardless of wheel/tire fitment. It is vital for extracting the most performance and longevity out of your tires, and without the proper amount the outer shoulders of your tires will wear out prematurely and running tire costs will dramatically increase.

 

Wheels

  • Front: 19x9" ET50 // Rear: 19x10.5" ET44
    • Available in SM-10 & VS-5RS
    • Popular Fitment

Tires

  • APEX Staff Pick: Front: 255/35-19 // Rear: 285/35-19
    • Direct fit  
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Bridgestone RE-71RS (200 TW), Michelin Pilot Sport Cup 2 240 Connect (240 TW)
    • R-Compound: No options currently available
    • Semi-Slick: No options currently available
  • Alternative 1: Front: 265/35-19 // Rear: 285/35-19
    • Camber plates and a minimum of -2.5º of front camber is recommended 
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Michelin Pilot Sport Cup 2 240 Connect (240 TW), Goodyear Supercar 3 (220 TW)
    • R-Compound: Goodyear Supercar 3R (100 TW), Toyo R888R (100 TW)
    • Semi-Slick: No options currently available
  • Alternative 2: Front: 265/35-19 // Rear: 295/35-19
    • Camber plates and a minimum of -2.5º of front camber is recommended 
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Falken RT660 (200 TW)
    • R-compound: Michelin Cup 2 (180 TW)
    • Semi-Slick: Hoosier R7 (40 TW)
  • Alternative 3: Front: 245/40-19 // Rear: 285/35-19
    • Direct fit 
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Bridgestone RE-71RS (200 TW), Michelin Pilot Sport Cup 2 240 Connect (240 TW), Goodyear Supercar Eagle 3 (220 TW)
    • R-Compound: No options currently available
    • Semi-Slick: No options currently available
  • Alternative 4: Front: 255/35-19 // Rear: 305/30-19
    • Direct fit
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Michelin Pilot Sport Cup 2 240 Connect (240 TW)
    • R-compound: Michelin Cup 2 (180 TW)
    • Semi-Slick: No options currently available
  • Alternative 5: Front: 265/35-19 // Rear: 305/30-19
    • Camber plates and a minimum of -2.5º of camber is recommended 
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Michelin Pilot Sport Cup 2 240 Connect (240 TW), Yokohama AD08R (200 TW), Goodyear Supercar 3 (220 TW), Falken RT660 (200 TW)
    • R-Compound: Toyo R888R (100 TW), Michelin Pilot Sport Cup 2 (180 TW), Nankang AR-1 (100 TW), Goodyear Supercar 3R (100 TW)
    • Semi-Slick: No options currently available

 

Wheels 

  • Front: 19x9" ET50 // Rear: 19x11" ET45 or ET46
    • Available in SM-10, EC7RS, VS-5RS
    • Popular Fitment

Tires

  • APEX Staff Pick: Front: 265/35-19 // Rear: 295/35-19
    • Camber plates and a minimum of -2.5º of camber front and rear is recommended
    • Rear wheel and tire will slightly poke beyond the rear fenders with wide tire compounds like RT660 & Hoosier R7. To prevent rubbing under compression a mix of negative camber and fender rolling may be required.  
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Falken RT660 (200 TW)
    • R-compound: Michelin Cup 2 (180 TW)
    • Semi-Slick: Hoosier R7 (40 TW)
  • APEX Staff Pick: Front: 265/35-19 // Rear: 305/30-19
    • Camber plates and a minimum of -2.5º of camber front and rear is recommended 
    • Tire compounds that run really wide will need negative camber in the rear and may poke a touch beyond the fender
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Michelin Pilot Sport Cup 2 240 Connect (240 TW), Yokohama AD08R (200 TW), Goodyear Supercar 3 (220 TW), Falken RT660 (200 TW)
    • R-Compound: Toyo R888R (100 TW), Michelin Pilot Sport Cup 2 (180 TW), Nankang AR-1 (100 TW), Goodyear Supercar 3R (100 TW)
    • Semi-Slick: No options currently available
  • Alternative 2: Front: 255/35-19 // Rear: 305/30-19
    • Front is a direct fit
    • Tire compounds that run really wide will need negative camber in the rear and may poke a touch beyond the fender
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Michelin Pilot Sport Cup 2 240 Connect (240 TW), Yokohama AD08R (200 TW)
    • R-compound: Michelin Cup 2 (180 TW)
    • Semi-Slick: No options currently available
  • Alternative 3: Front: 275/675-19 // Rear: 305/690-19
    • Camber plates and a minimum of -2.5º of front camber is recommended 
    • Racing Slick: Pirelli P Zero DH

 

Wheels 

  • Front: 20x9" ET50 // Rear: 20x11" ET50
    • Available in VS-5RS
    • Clears 410mm PCCB

Tires

  • APEX Staff Pick: Front: 245/35-20 // Rear: 295/30-20
    • Factory GT4 Tire Sizes
    • Direct Fit
    • Max Performance Summer: Michelin PS4S (300 TW)
    • Extreme Performance Summer: Goodyear Supercar 3 (220 TW)
    • R-Compound: Michelin Pilot Sport Cup 2 N1 (180 TW), Dunlop Sport Maxx Race 2 N1 (80 TW)
    • Semi-Slick: Hoosier R7 (40 TW)

 

 

18" Setup - Hardcore Track & Race

All-out performance for fastest lap times

Many GT4 owners are inspired by the GT4 Clubsport and inquire about running an 18" wheel and tire configuration. 18" wheels will reduce rotational mass, decrease running tire costs, and open you up to racing slick compounds only offered in this diameter, however, the standard 6 piston 380mm steel brakes found on the road-going GT4 will not clear an 18" wheel barrel from any wheel manufacturer. 

To overcome this barrier, owners will purchase and install PFC brakes very similar to the brakes found on the Clubsport. The PFC BBK is quite an investment, therefore, many owners have opted to go with factory 997.2 GT3/GT3RS 6 piston 380mm front brakes as a more cost effective solution. The good news is that our 18" EC-7RS & VS-5RS forged wheels offer massive brake clearance, and were engineered specifically to clear both the PFC Sport kit (pn 0.380.0001/2 Sport), as well as the factory 997.2 GT3/GT3RS brakes. * They do not clear the PFC Race kit. 

 

Wheels 

  • Front: 18x9" ET46 // Rear: 18x10.5" ET44
    • Available in EC-7RS & VS-5RS

Tires

  • APEX Staff Pick: Front: 25/64-18 // Rear: 27/68-18
    • Factory GT4 Clubsport tire sizes
    • A minimum of -3º of front camber is recommended
    • Racing Slicks: Michelin
  • Alternative 1: Front: 265-645-18 // Rear: 305-680-18
    • A minimum of -3º of front camber is recommended
    • Racing Slicks: Pirelli DH
  • Alternative 2 Front: 265/35-18 // Rear: 295/35-18
    • A minimum of -3º of front camber is recommended
    • Extreme Performance Summer: Yokohama A052 (200 TW)
    • R-compound: No options currently available
    • Semi-Slick: No options currently available

Additional Resources

Brake Clearance Information

In the engineering phase of wheel development we 3D scan factory brakes and review 2D aftermarket brake templates in order to optimize our barrel profiles and spoke curvatures. As a result, our wheels offer massive brake clearance so you can run the smallest possible wheel diameter. The following brakes have been tested and confirmed to clear our wheels.

  • Factory Steel 6 piston 380mm - Clears 19" SM-10, EC-7RS & VS-5RS
  • Factory PCCB 6 piston 410mm - Requires 20" wheels
  • AP Racing 13.01.10083  CP9661 6 piston 394mm - Clears 19" SM-10, EC-7RS & VS-5RS 
  • PFC 0380.0001/2 Sport 6 piston 380mm - Clears 18" EC-7RS & VS-5RS 

Should I Dial in Negative Camber, and How Much is Right for me? 

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Whether you are a casual weekend track warrior that still enjoys your car on the street, or a hardcore racer competing for a spot on the podium, negative camber is a vital part of chassis setup that has many benefits. Not only will adding negative camber create more room for wider wheel and tire configurations (when dialed in through the top hat / camber plate), it more importantly improves handling, turn-in and tire longevity. Learn more in our blog article, The Positives of Negative Camber.

 

Street w/ Occasional Track Use

Camber: -2º front, -1.8º rear

Toe: Zero front, 1mm toe-in rear (each side) 

 

Street w/ Frequent Track Use

Camber: -2.5º front, -2º rear

Toe: Zero front, 1mm toe-in rear (each side)

* A small amount of toe-out can also be used up front to improve turn-in, but it will scrub a little speed on the straights. 

 

Aggressive Track

Camber: -3º front, -2.5º rear

Toe: Zero front, 2mm toe-in rear (each side)

* A small amount of toe-out can also be used up front to improve turn-in, but it will scrub a little speed on the straights. 

 

 

Still have questions?
Fill out our Fitment Recommendation form
Call us: 925-245-0773
Email us: support@apexraceparts.com

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