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Autocross Mods

Discussion in 'Gen 3 Prius Accessories and Modifications' started by toyotechwv, Apr 6, 2016.

  1. granTORRESmo

    granTORRESmo Senior Member

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    Awesome! U got 2nd place in your class?
     
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  2. toyotechwv

    toyotechwv Toyota Technician

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    Sure did. I added a link ^^^ to the full results.

    SM-G900V ?
     
  3. Justdidit

    Justdidit LVNPZEV

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    What kind of car was it that got first?
     
  4. toyotechwv

    toyotechwv Toyota Technician

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    1996 240sx on Bridgestone RE -71R's. The Prius could've beat him but I'm a bit rusty and didn't have it in me this time.

    SM-G900V ?
     
  5. Justdidit

    Justdidit LVNPZEV

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    Do you think you noticed the 8.3% difference in size... acceleration wise?
     
  6. toyotechwv

    toyotechwv Toyota Technician

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    Oh yes. Acceleration was noticeably different. I think that was my problem LOL. Corner entry speeds were higher than I anticipated and ended up with gobs of understeer. I started with 42 psi in the tires and made adjustments each run in search for more front grip and less rear, ended up with 51 front and 46 rear and it rotated nicely. Last 3 runs I clipped a cone though.

    SM-G900V ?
     
  7. Justdidit

    Justdidit LVNPZEV

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    Crud, i was almost hoping it wasn't so noticeable. I don't think I'll be able to change my tire size much to improve the gearing.

    Capture.JPG

    I haven't tried a 16" wheel yet, but I'm pretty sure the new IS350 caliper won't clear anything under 17"
     
  8. granTORRESmo

    granTORRESmo Senior Member

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    Oh wow, I thought higher psi in the rear and lower in the front rotates better. Good thing your sharing all this info
     
  9. toyotechwv

    toyotechwv Toyota Technician

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    The issue with low psi in front is the tires will roll under and onto the sidewall. Without the addition of the TRD sway bar I likely would've needed even higher pressure in the rear.

    SM-G900V ?
     
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  10. toyotechwv

    toyotechwv Toyota Technician

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    How heavy are your wheels?

    SM-G900V ?
     
  11. Justdidit

    Justdidit LVNPZEV

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    Picked up a set off Kijiji for $100

    Drag wheels DR31
    Size: 17 X 7
    Bolt Pattern:5 X (100 / 114.3)
    Offset: 40
    Weight: 19lbs

    Originally these were just to replace my winter steelies - but I thought I could use them also for strictly for AutoX.

    My daily wheels are:

    ADR S07R Wheels
    Size: 19x7.5
    Bolt Pattern: 5 X 100
    Offset: 42mm
    Weight: +25lbs (haven't weight for specifics but def heavier than my steelies or DR31s.

    Both of these are SUPER heavy considering the 15s and 16s specs..

    15 inch base: 15X6 14.3 lbs
    16 inch Touring: 16X6 15.2lbs
     
  12. toyotechwv

    toyotechwv Toyota Technician

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    True but you can fit a wider tire which will benefit ypu more in autocross. I wish the Dunlops I have were available in a 215 or a 225 width for a 15" tire. What a Prius lacks in power you can make up in grip. If you can maintain I higher average speed on course then you won't have to try to accelerate from lower speeds. That's what hurt me yesterday.....loss of momentum.

    SM-G900V ?

    Tire on the left was on the front, the other on the rear. You can clearly see where the front tire rolled under and the rear was basically perfect as far as maintaining tread contact.

    uploadfromtaptalk1462227194454.jpeg

    SM-G900V ?
     
  13. granTORRESmo

    granTORRESmo Senior Member

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    Hey so did you go faster with rear swaybar vs. RAV4 front swaybar?
     
  14. toyotechwv

    toyotechwv Toyota Technician

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    Did I go faster.....I would say yes. I noticed the car transitioned very nicely on the slalom sections and I would attribute most of that to the TRD rear bar. I did swap the OEM front bar back before the event since 2 upgraded bars isn't legal in my class. Before my next event I'm gonna try to get a bit more negative camber in the front as well.

    SM-G900V ?
     
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  15. Starbrand

    Starbrand Senior Member

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    found some semi-old videos. almost looks like RWD from the 2nd and 3rd turns. if you time them just right when hitting play on both, they're pretty much neck and neck. but blue prius accidentally re-enters for some odd reason.
     
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  16. Dylan Doxey

    Dylan Doxey Senior Member

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    I think it's like at the golf course when you replace your divots.
    The blue car had to go back and reset the cone he knocked over. :whistle:
     
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  17. RightOnTime

    RightOnTime Senior Member

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    That is some amazing videos! ^^


    #PriusGang
     
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  18. BigBear2010

    BigBear2010 Member

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    how they can drift like that? Hand brake?
     
  19. toyotechwv

    toyotechwv Toyota Technician

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    Quick update, I've just completed my 6th event of the year. I've had three 2nd place finishes in class and three 1st place finishes in class. This past weekend I won my class in the Virginia Autocross Championship/Commonwealth Games. I was also featured on a 2 part podcast on racershq.com. Get out there and autocross those hybrids!!!!!!
    uploadfromtaptalk1471466071415.jpeg uploadfromtaptalk1471466091117.jpeg uploadfromtaptalk1471466100350.jpeg uploadfromtaptalk1471466115035.jpeg

    SM-G900V ?
     
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  20. Justdidit

    Justdidit LVNPZEV

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    Sounds like the new tires did well with your driving and the new alignment!

    Posted via the PriusChat mobile app.