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GenII Brake Upgrade w/o breaking the bank?

Discussion in 'Gen 2 Prius Accessories & Modifications' started by Justdidit, Oct 17, 2012.

  1. Justdidit

    Justdidit LVNPZEV

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    Has anyone attempted a Brake Swap on the G2 in the SoCal? ... That is w/o spending $3K on the KSport kit?

    [​IMG]

    Here has been my line of thinking lately. Having some brackets fab'd up like this:

    [​IMG]

    and going with some OEM lexus hardware...just having the rotors redrilled to 5x100 instead of the 5x114.3

    Option 1: Calipers and rotors from the '06 IS350 rotor would be 333mm (13.1")

    [​IMG]

    [​IMG]

    Option 2: Or a more common swap.. the UCF30 Calipers and rotors from the '06 LS430 - rotor would be 315mm (12.4")
    [​IMG]

    [​IMG]

    Seen this from a site in Japan: TOM's BBK... Looks really similar to the UCF30 caliper

    [​IMG]

    How hard could it be??
     
  2. Justdidit

    Justdidit LVNPZEV

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    Cost???

    IS350 333mm swap:
    Brackets: ?TBD
    Rotors: $55 x 2 partsgeek.com
    Redrilling: cheap?
    Calipers: $120 x 2 partsgeek.com ($55 core charge return if u can find some old crummy ones to send back)

    $350 w/o a refund on cores plus drilling fee and fab fee for bracket

    LS430 315mm swap:
    Brackets: ?TBD
    Rotors: $37 x 2 partsgeek.com
    Redrilling: cheap?
    Calipers: $107 x 2 partsgeek.com ($55 core charge return if u can find some old crummy ones to send back)

    $288 w/o a refund on cores plus drilling fee and fab fee for bracket
     
  3. Justdidit

    Justdidit LVNPZEV

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    OF COURSE, this only would apply to those interested in improving braking while AUTOXing. :)
     
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  4. Justdidit

    Justdidit LVNPZEV

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    Also just wanted to throw it out there that these are monoblock all aluminum... so relative lightweight compared to some... The UCF30 is 10.5lbs w/ pads loaded. Not sure yet about the IS350 calipers.
     
  5. sfv41901

    sfv41901 Masta S

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    Just think of the $$$ return if u designed some brackets
     
  6. Justdidit

    Justdidit LVNPZEV

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    hmmm... :)
     
  7. Justdidit

    Justdidit LVNPZEV

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    If someone was worried about the re-drilling of the holes... you could swing this: 2005 Subaru Legacy GT has a 5x100 bolt pattern and can come in 316mm. :) Lil more pricey ($46 ea) but...no worries of cracking between holes due to redrilling the bolt pattern.

    [​IMG]
     
  8. Justdidit

    Justdidit LVNPZEV

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    UCF30 would require 55mm of clearance between the wheel and the rotor based of these specs:

    [​IMG]
     
  9. Daves09prius

    Daves09prius Active Member

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    you could keep the stock calipers, and replace the rotors with some drilled and slotted or dimpled and slotted + some EBC green stuff or yellow stuff pads.
     
  10. Daves09prius

    Daves09prius Active Member

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  11. Justdidit

    Justdidit LVNPZEV

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    I'm looking for more bit. Once i go with larger wheels, I will need more stopping power. Don't think I'll be happy with the stock 1 [pot - 10" (254mm) brake setup. With a 4 pot setup and more disc/pad surface area from a 316-333mm setup will definitely help.
     
  12. Justdidit

    Justdidit LVNPZEV

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    I've tried the EBC greestuff and actually had better luck even with Bendix pads... But that was on a Civic w/ a mini-me swap. The cross-drilling/slotting has never shown to help me out much, but I'm not THAT serious of an AutoXr... Definetly more of a Show than Go for me. :)
     
  13. Justdidit

    Justdidit LVNPZEV

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  14. Justdidit

    Justdidit LVNPZEV

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    Found out that the VW R32 & Audi TT have the same bolt pattern (5x100) and use a 334mm rotor... Might be a good option for the IS350 caliper swap. I'd prefer not to have to redrill the rotors if possible.

    [​IMG]
     
  15. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    I just don't see the ROI on this??? The Prius only uses the brakes from 7-0 mph (in typical braking).
     
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  16. Justdidit

    Justdidit LVNPZEV

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    Agreed. LOL
    Or those who have added weight to their car by adding larger wheels (like I am - 19") - don't want to lengthen my stopping distance...but rather shorten it even more than stock. I LOVE having great braking power.

    There are other mods i plan on doing that may have zero ROI to most... but hey modding your Prius isn't always about ROI. :)
     
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  17. Britprius

    Britprius Senior Member

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    Have you thought about the effect this will have on vehicle stability control, it will probably put you into a spin instead of getting you out of one.
     
  18. Agent J

    Agent J Hypoliterian

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    Since you mentioned beforehand that this will be bit more "show" than "go", your plan does look good on paper and it is a start. However, as with all natural-born gearheads like us, this will just be the start of more numerous upgrades to squeeze out precious seconds out of the runs as it can get addictive.. =P

    I agree with Britprius. With your current suspension setup with lowering springs/stock shocks, etc, the car would still dive considerably on hard braking transferring all the weight up front making the rear end lift, lose traction, lock or activate ABS prematurely. Soon you'll end up wanting to change to racing coilovers, bigger front sway bars, upgraded bushings, camber kits, upgraded rear brakes, brake bias controller, bigger engine(!), etc. :) Also, since you're probably one of the first to do this, it would be interesting to know how the car handles the transfer of braking duties from the MGs to the bigger brakes. I'm hoping it's not too abrupt that would make the car a tricky to handle in a AutoX course.

    It sure is a fun way of modding and experimenting with a Prius. I'd definitely do the same if I had the money. But I'd choose to go for brake pads and suspension tweaks first before going all out on big brakes since you won't be able to accelerate that fast on a stock engine and go far in a short AutoX course to justify significantly more braking power. Bigger brakes are only needed to counteract bigger HP gains when you modify the engine. What you'll need to shave a lot of time is how you approach the corner and how the car will go fast around a corner, not how fast the car will stop before a corner. ;)

    Do keep us posted on your project, nonetheless! : )
     
  19. Daves09prius

    Daves09prius Active Member

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    enter the corner slow, exit the corner fast = :)
    enter the corner fast, exit the corner slow = :(
     
  20. maestro8

    maestro8 Nouveau Member

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    On this note, why not just do some painting in the wheel well... paint the calipers, the rotor hats, maybe even put a sticker on the caliper. Mod done, and no impact to safety.

    I hate to disappoint you, but all you're going to get here is "wow it feels great!" I've yet to see a single dyno sheet, lap time, skidpad test, any hard number for that matter, anywhere on this site. And prepare for the flames if you dare ask for any more evidence.

    I'd think the ICE cutting out just before a turn would make the car tricky to handle on any course.

    "Need" isn't the driver here. "Want" is. These cars get groceries, I'm dubious that anyone has so much as turned a single lap in them...