KentBigDog’s 2017 Mazda MX5 RF Track Car

2017 MX5 RF LE

My Mazda MX5 is not a daily driver. It’s street legal and I do occasionally drive it on an errand but it’s a track-focused car. I drive 60 miles round trip every time I go to the track and it isn’t uncomfortable at all. A bit noisy for sure. I wouldn’t be afraid to drive it across the country though. It is very reliable. In case you’re wondering, I’m still on the original V2 transmission.

Engine / Powertrain / Exhaust

Suspension

  • Height: 12.8″ front, 13.0″ rear
  • Alignment:
    • Camber: -3.5°F, -3.0°R
    • Toe: 0.0 F&R
    • Caster: 6.4°
  • Karcepts ND Front Camber Bushings
  • Ohlins Road & Track DFV Coilovers from Miataspeed
  • Swift Springs
    • Front: 10kg:560lbs/in
    • Rear: 5kg:280lbs/in
  • Screw-in Spherical Bearing Inserts using stock top hats
  • Karcepts Anti-roll Bars Front and Rear (0.120f / 0.095r)
  • GWR Shock Tower Brace
  • Paco Sway Bar Supports

Brakes

  • Front: StopTech C43 BBK
    • Caliper weight 4.3lbs
    • Bi Slot floating rotors on race hats (28.001.1118.CT.87)
    • Optional Stainless Steel Piston Noses for reduced heat transfer
    • Rotors are 31mm wide, weigh 13.2 with hat
    • DR21 or 7416 pad shape
  • Verus Brake Cooling Duct Kit ⇒ Installation video
  • Rear: Wilwood Powerlite 4-piston in rear
    • Pad 7912 / Pad area 5 sq in
    • MiataSpeed 2-Piece Rear Rotors
  • Speed Bleeders (SB1010S)
  • Stainless Steel Brake Lines Front & Rear
  • Raybestos ST-43 pads
    • Front Part #: ST43R701T20
    • Rear Part #: ST43R1000T13
  • SakeBomb Garage Variable Brake Booster Controller ⇒ My review
  • Repositioned Rear Brake Hard Lines ⇒ Photos

Wheels / Tires

  • Falken RT660 245/40-17 (great 200TW tires)
  • MiataSpeed RZ+ Forged Wheels 17×9 +45
  • ARP Wheel Studs
  • Muteki SR48 Black 12mm x 1.5mm Steel Open End Lugs
  • Rear fenders are rolled

Interior / Electronics / Seats / Harnesses

Exterior / Aero

  • Race Louvers Heat Extractors ⇒ Installation video and photos
  • Verus Rear Diffuser ⇒ Photos with SSTT
  • Good-Win Racing Transmission Cooling Air Scoop
  • Mazda Motorsports GMX5 Tow Straps
  • XPEL Door Edge Guard
  • CravenSpeed Door Bushings
  • Shorty Antenna
  • Hella Sharp Tone Horn set
  • LED Light Conversion Interior and Exterior
  • Smoked Side Repeaters
  • CarbonMiata Spyder Grill
  • Plasti-dipped Emblems Front and Rear
  • Custom Painted Engine Bay
  • Removed Shark Fin
  • Sound Tube Delete
  • Hood Struts
  • Stickers. Lots and lots of stickers.

Maintenance / Fluids and Parts

Past Stuff

  • Nankang AR-1 245/40-17 (really like these 100TW tires)
  • Good-Win Racing 12.88” Wilwood Dynapro 6-piston Big Brake Kit (knowing what I know now, I would go straight to the StopTech C43 kit.)
  • Titan7 Forged T-R8 17×9 +45 (good wheels, no issues, I just liked the MiataSpeed RZ+ wheels having a bit more material and hopefully more strength)
  • Springs 8kg/4kg
  • Tires: Dunlop Direzza Z3 235/40-17 (not a fan)
  • Tires: Falken Azenis RT615K+ 235/40-17 (great learning tire)
  • 949Racing 6UL wheels (not a fan, one broke loose from my car and the other 3 wheels all had cracks) ⇒ Photos
  • Dual Electronics XGPS160 BT GPS receiver

Wants

Last modified August 26, 2021

Some Video

A couple videos from my Youtube channel.

Join In

Interested in tracking your Mazda MX-5 2016+ car? Join us on the Facebook Miata ND Track & HPDE Discussion Group.

12 thoughts on “KentBigDog’s 2017 Mazda MX5 RF Track Car

  • ray
    May 30, 2021 at 9:40 am

    Can you comment on the StopTech C43 brake kit vs. the Goodwin 12.88 BBK? I was thinking of purchasing the Goodwin product.

    Thanks,

    Ray

    • KentBigDog
      May 30, 2021 at 4:23 pm

      Hey there Ray, I wrote a bit on my brake system journey recently. Take a look at this: https://www.kentbigdog.com/my-brake-system-journey/ and let me know if you have questions. I’m happy to fill in the blanks. –Kent

  • Brian Tobin
    April 5, 2021 at 3:40 pm

    Kent,

    I recently purchased a 20’ RF and found your blog. I bought mine with the 4/7 Ohlins, I see you switched to the stiffer springs, how much improvement did you see. I also noticed that you switched from the Titan 7 wheels, wondering why and are your new wheels better? I want to buy a track aet of wheels/tires. Also, what would you recommend dor too end tires.

    Thanks,

    Brian

    • Kent
      April 5, 2021 at 5:05 pm

      Hey Brian, for track use the stiffer springs have been great. If you are primarily street driven with some track days, the 4/7 arrangement should work just fine. I have nothing against the Titan wheels. I think they are very good. I’m just slightly more comfortable with the Miataspeed wheels that have a bit more material. Miataspeed warranties their wheels even if you use them on track too. The 245/40 RT660 tires on a 17×9 wheel are great. You can also go with a 235/40 on a 17×9 and not have to roll your rear fenders.

    • Brian Tobin
      April 30, 2021 at 2:15 pm

      Kent, thanks for the response. Another question, what are the benefits to switching out to the OSGiken LSD from the stock one., thanks Nrian

    • Kent
      April 30, 2021 at 8:22 pm

      My car didn’t have an LSD, that’s why I went with the OSGiken. Personally, if I had the stock LSD, I’d probably stick with it.

    • Brian
      May 2, 2021 at 10:15 am

      Thanks Kent, that makes sense since you did not have an LSD. I don’t want to roll fenders at this time so I plan to stay with 235/40/17 for my 9″ rims. I am looking for a top notch track tire and that tire size limits choices a lot. I noticed that you liked the AR-1s and you currently have the RT 660s. Both come in the size I am looking for but since you have history with both what would you recommend? On my NC I had NT-01s which is my only 100W tire I have used but I think they are a bit outdated now. I also read good things about the A052s but they only come in 235/45 and I’m not sure if that will create rubbing issues…

    • Kent
      May 2, 2021 at 1:26 pm

      If you can find the RT660s, they are a great tire. They’ve been sold out now for a few months but are supposed to be available again soon. The Nankang AR-1s are an awesome tire as well. Pretty equal really so I’d let availability and price be your guide. If you are going to use the car as a daily driver, the RT660 would probably last a bit longer. Nankang has a new tire in the US, the CR-1. I’d consider them as well. I haven’t tried them yet but I believe they are a 200TW tire and have been getting good reviews.

  • Kevin
    January 29, 2021 at 12:47 am

    What alignment specs are you running? I want to run 245/40 17 tires on 17×9 et45 wheels. I know I’ll have to roll my rears, but what what about your fronts?

    Thank you

    • Kent
      January 29, 2021 at 10:18 am

      My current specs are

      1. Camber: -3.0F, -2.5R
      2. Toe: 0.0 F&R
      3. Caster: 6.0

      I didn’t have to roll the fronts. They are aluminum fenders anyway so pretty damn hard to roll.

  • Martin Urcola
    February 26, 2020 at 1:52 pm

    Kent, thanks for sharing, I`m the one that wrote you through the Youtube video at Eagles Creek. Very interesting set of mods, some completely new (and I`d been researching…). So far I`m at a very early stage, did 4 HPDEs and more comming. Just have RCF brake fluid, Michelins SS (not a track tire, though), Borla exhaust just for sound and in order to remove the resonator, Ferodo DS2500 pads (I`ve the Club Brembo version that includes brakes, BBSs, eibach, Blisteins and LSD). Need to think my next move: should I invest in this one or move into the 2019 Club, earn some 26 HP and start from there? I just bought a MB C43 AMG for conmuting and ocassionaly for COTA, and my wife won`t be very happy if I swap another car this year. In your opinion, if you have to start all over again, which of this mods will help you to earn more in terms of laptime? Not because I`m racing against anybodyelse, but because probably this will be the result of a more trackable set up…

    Thanks again,

    Martin

    • Kent
      February 26, 2020 at 4:02 pm

      Hi Martin, the best way to improve laptime is to spend time improving the driver! The Club Brembo is a more than capable track car as-is. I’d run it for a while to see what you like and don’t like. If you are dying to make a change, upgrade the tires to a more capable track tire.

      If funds aren’t an issue, then yes, I’d get a 2019 or later. Might as well start with more power. But I’d run what you have for a while, put some miles on it before you trade it in.

      Join us on the Facebook Mazda ND Track Junkies page for more ideas and like minds.

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