Kumho V730 Update | Are They Finally Dead...?

Поділитися
Вставка
  • Опубліковано 8 вер 2024
  • After 1.5 years, 18+ autocrosses, 6 TT track weekends, 3 lap records, and 4 top-10 PAX finishes, are the Kumho V730s finally starting to show their age? In this video we explore the remaining tread depths and durometers and try to answer why the #512 RX-8 was loose handling at the last event. Was over-driving to blame? Or might the Kumho V730s undergo a rubber compound change below 2/32" (vice being good to the cords)? Tune in to find out!
    Front tread depths: 2.5/32"
    Rear tread depths: 2.0-/32"
    Durometers: About 65 shore all around
    Current thoughts:
    - Kumhos get faster as they wear, to a point...
    - Retain good warm-up time (don't heat cycle badly)
    - As they wear, they like lower and lower pressures. I run 26psi at track, 24-25 psi at autocross (hot).
    QUESTIONS OR COMMENTS? LEAVE THEM BELOW.
    SUBSCRIBE FOR MORE TIME ATTACK, TRACKDAY, AUTOCROSS, AND KARTING VIDEOS
    #512 Mazda RX-8 Major Modifications
    - 32mm front swaybar, redrilled OEM rear swaybar
    - Bilstein B6 dampers with Racing Beat springs
    - AEM intake (STX modded), underdrive pulleys
    - 255/40/17 Kumho V730 on 17x9 +35 TRM FF10

КОМЕНТАРІ • 30

  • @jasondoulkeridis6202
    @jasondoulkeridis6202 Рік тому +3

    Great feedback, I might try a set!

    • @rx8matt
      @rx8matt  Рік тому +1

      I think I'm going back to them. They don't have the last few tenths but they are so fun and long lasting

    • @user-cd3hd1ob5m
      @user-cd3hd1ob5m Рік тому

      Do these run smaller ? More narrow?

    • @jasondoulkeridis6202
      @jasondoulkeridis6202 Рік тому

      @@user-cd3hd1ob5m I have a set of 245/40r18 ready to fit, ping for feedback end of the month

    • @user-cd3hd1ob5m
      @user-cd3hd1ob5m Рік тому

      @@jasondoulkeridis6202 measure the width ? And measure other 245?

    • @rx8matt
      @rx8matt  Рік тому

      @@user-cd3hd1ob5m yeah it's a pretty nice range of sizes down to 205 I think

  • @_Mike_D_
    @_Mike_D_ 2 роки тому +3

    I just ordered a set of these for a September event. Will be interesting to see how they stack up against the federals I was running and the conti’s I mainly use for wet days.

    • @rx8matt
      @rx8matt  2 роки тому +2

      The V730s should be significantly better than both of those. LFX should have no issues putting the power down! Looking forward to your feedback. Although I think I'll try the falken rt660 next, just to try something different

    • @richardrose5776
      @richardrose5776 Рік тому

      Well, how were they?

  • @MrJspecefini
    @MrJspecefini Рік тому

    I came from watching the tire rack video where they tested these alongside many other high performing tires and these ran quite quick. Best of all, these are less than $200 for 265/35/18’s while the other ones were $350 or more. Definitely will try these for my r33 gtr.

    • @rx8matt
      @rx8matt  Рік тому +2

      That's the exact size I'm running now. I actually went back to kumhos after trying A052

  • @JNS2k
    @JNS2k 2 роки тому +1

    Just ordered a set of v730s - 245/40s for my 7.5 wide street class wheels. we will so how this goes

    • @rx8matt
      @rx8matt  2 роки тому

      They work great in a pinch. Ha, see what I did there? But yes I think they are the best choice for limited wheel width and limited camber

  • @mattbell6908
    @mattbell6908 4 місяці тому

    You mentioned 26psi pressures for track is that your cold pressure or target pressure?

    • @rx8matt
      @rx8matt  4 місяці тому +1

      Target hot on my car. Ymmv

    • @mattbell6908
      @mattbell6908 4 місяці тому +1

      @@rx8matt coming from rt660 in 245/40/17 ran those at 23 cold. So sounds like the kumho should be close to that

    • @rx8matt
      @rx8matt  4 місяці тому

      @@mattbell6908 are you tracking or autocross? For autocross I usually only see around 4psi gain. At track it can be more like 8-10psi gain

    • @mattbell6908
      @mattbell6908 4 місяці тому

      @@rx8matt tracking

    • @rx8matt
      @rx8matt  4 місяці тому +1

      @@mattbell6908gotcha, yeah 23 cold is probably a decent starting point, warm them gradually on the out lap

  • @Phuong_Nguyen_
    @Phuong_Nguyen_ Рік тому

    Could I use these tires even if I doubt autox? I just want something sticky to bring the best out my coilovers

    • @rx8matt
      @rx8matt  Рік тому +1

      Sure. But they ride pretty firm and will make coilovers feel even more harsh. For sporty street use the Michelin pilot ps4 and continental extreme contact sport are great choices. Better in rain too

  • @nicholaskunen6504
    @nicholaskunen6504 Рік тому

    Hi! I was wondering what kind of camber you were running for these tires

    • @rx8matt
      @rx8matt  Рік тому

      I ran -3.0 and it was plenty .. maybe even too much! But my car has fantastic suspension geometry and weight distribution