This is why you don't run stock suspension...

Discussion in 'Road Racing Forum' started by domesticpower, Jul 28, 2019.

  1. domesticpower

    domesticpower Track Addict

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    Boss 302 AMP T9 Braking Nose Dive.jpg

    Still managed to go home with something, though. I know the car’s not clean, but this ain’t no show car trophy! Got 5th fastest raw time of the day, 3rd overall adjusted for class out of 18 competitors. No one ahead on raw time was in a lower class and beat out a few in higher classes on raw time.

    Boss 302 3rd place overall time attack.jpg

    Aside from a couple of cars in the bottom half of the field, no one was running stock suspension and most were on coils. Now, who wants to donate a set of coils to go chase that 1st place overall trophy??
     
  2. ChrisM

    ChrisM No bad days.

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    Nicely done! I love those pics, especially the dirty car. You must be one helluva driver!
     
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  3. domesticpower

    domesticpower Track Addict

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    Thanks Chris, appreciate that!! I like to think I'm alright... but don't we all?? haha
     
    Last edited: Jul 29, 2019
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  4. Bill Pemberton

    Bill Pemberton TMO Addict

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    Just goes to show what a good set of rubberized air filled donuts will do ----- not just cornering improvement , more stopping power!!! Solid pic and it does probably help your turn in with all that weight on the front, ha,ha.
     
  5. c2fx

    c2fx TMO Intermediate

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    Nicely done! I'm assuming the new rim/wheel combo made your dive much worse than before? Any other stock suspension observations before/after adding 305s?
     
  6. domesticpower

    domesticpower Track Addict

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    Thanks! Yea, nose dive is noticeably worse, as is body roll and movement in general. Car is also much more neutral compared to before (was also a square setup but 285's), likely due to the 2.5"+ wider track up front. I'm used to trail braking into several corners on our track. Doing the same now kicks the back end out in corner entry. The extreme nose dive is likely a factor too by unloading the back end even more.
     
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  7. Bill Pemberton

    Bill Pemberton TMO Addict

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    Mustangs and M3s, folks just can't figure out how cars with their body roll and tendency for a bit of nose dive are soooo fast?? Makes a lot of us look more skilled in other's eyes than we really are ,ha,ha!
     
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  8. Coz

    Coz TMO Race

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    Upgrading to the 13-14 GT500 rear rotors (via adapter or via GT500 axle bracket) may also help reduce dive since the back end will share a bit more of the braking effort.
     
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  9. blacksheep-1

    blacksheep-1 TMO Addict

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    nothing wrong with dive...

    [​IMG]

    or squat..

    [​IMG]


    and those are on hi zoot Penske coilovers
     
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  10. Coz

    Coz TMO Race

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    I'm sure he's driving at 10/10 and is experiencing some high g's due to his speed and his slicks. But is the same degree of dive/squat acceptable while using a 200TW tire?

    I'm also guessing that the body movement on AJ's car was a bit more gradual than stock suspension would allow.
     
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  11. BigWillowlittlemustang

    BigWillowlittlemustang TMO Beginner

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    would a torque arm help with that nose dive?
     
  12. blacksheep-1

    blacksheep-1 TMO Addict

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    I would think you would want all you could get to make the tire stick, and that suspension is pretty stock, nothing trick at all, with the exception of the shocks.
    I think this is a pic of the car with the relocation brackets installed, which sounded good on paper but were later discarded. Nothing to write home about.

    [​IMG]
     
    Last edited: Aug 3, 2019
  13. domesticpower

    domesticpower Track Addict

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    Haha yea, let's keep it that way!

    Thanks Coz, I'll keep those in mind. Likely will come after coils.

    Quite a bit of body roll too visible in the second picture!
     
  14. Grant 302

    Grant 302 OPM Spent: $665,833 Moderator

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    *That's* not body roll. :D

    The roll angle is actually smaller than visible in 2D on this picture because of the point-of-view angle relative to the car.

    #23 body roll.jpg
    I think the framing (tilt) of the shot and the visible squat make it seem like more roll than it is. I'm guessing there's almost full diagonal weight transfer from the RF to the LR tires. Maybe 800+ lbs?

    *This* is body roll! ;)
    [​IMG]
     
  15. ChrisM

    ChrisM No bad days.

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    Sweet. New desktop photo.

    Also, I’m guessing that eliminating body roll entirely isn’t the goal, whereas making it manageable and learning how to manage it is. I think I read that in a book somewhere.
     
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  16. Coz

    Coz TMO Race

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    Crocodile Dundee joins TMO!
     
  17. blacksheep-1

    blacksheep-1 TMO Addict

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    take note of the left rear tire as well, these were only little baby 275s and a fairly hard compound.

    [​IMG]
     
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  18. Bill Pemberton

    Bill Pemberton TMO Addict

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    No joke BS1, there are bicycle tires out there bigger than that I bet?
     
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  19. Norm Peterson

    Norm Peterson Corner Barstool Sitter

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    Only the "tail rise" portion. What that side view picture shows is vehicle pitch motion and that it's partly nose dive and partly tail rise. The front suspension will still compress just as far under the same deceleration.

    Depending on specifics, a TA could certainly reduce the "pitch", but not the "nose dive" part.


    Norm
     
  20. Grant 302

    Grant 302 OPM Spent: $665,833 Moderator

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    "depending" and "could" are very important parts of that statement. I see it as 'true' when compared to stock geometry, but it's easy enough (IMO) to setup trailing arms to prevent 'tail rise' compared to a torque arm, and stay out of brake-hop conditions.
     

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