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Discussion Starter #1
I am getting a Rotora BBK for my turbo set up. I was wondering what i should do with my rear brakes... it will look weird if there just my stock brakes? is there a rotora rear brake upgrade? Thanks!

(very close to done with turbo set up)
 

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theformat26 said:
I am getting a Rotora BBK for my turbo set up. I was wondering what i should do with my rear brakes... it will look weird if there just my stock brakes? is there a rotora rear brake upgrade? Thanks!
i'm in the same boat with you my friend except no turbo setup. i was thinking about just getting the slotted Rotora OEM sized rotors for the rear. i don't think that Rotora makes a BBK for the rear where you can still put the stock rim over. i know they have a rear BBK, but i think you are restricted to a 18" wheel. i know there are 2 sizes for the front BBK, 330mm and a larger size. the 330mm allows you to put the stock rim over it but you need a 5mm spacer
 

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Discussion Starter #3 (Edited)
im getting the BBK in the front, i dont want to waste my money no the rear. i jsut want to make it match the front, but of course not as big

also the rims i am getting are 18"
 

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Discussion Starter #4
anyone? sorry to be so pushy... just the faster i get this all organized, the faster i can get to work
 

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Rotora makes a 4pot RBBK for use with their 6pot FBBK. I believe its actually sold together as a kit.

On the same note, Endless, StopTech, and AP Racing also make 4 wheel BBKs for the IS.
 

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just go with Drilled & slotted rotors for the back... with an 18 in wheel it wont look "BAD" and the exopense of gettign a bigger RR brake setup out back PLUS the issues with the existing 4wheel Kits Brake bias and Ft/Rr Brake balance are to be considered.

from what i hear even with Stoptech's claim that they make specific changes to the rear setup o nthe 4wheel IS 300 kit to balance the brake power front & rear there is STILL an issue & two owners of their 4 wheel upgrade kits have not been happy with the brake bias..... Still TOO strong out back.... very easy to lock up/ No modulation.....


here are a few pics of my new 14 in Front Stoptech setup and my OEM sized rears.




 

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Discussion Starter #7
thanks thats what i needed edgy!
 

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Discussion Starter #8
i didnt want to spend the extra/ kind of useless money on a bbk on the back. are your rear's drilled and slotted? if so... did you paint your stock caliper?
 

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edgy said:
just go with Drilled & slotted rotors for the back... with an 18 in wheel it wont look "BAD" and the exopense of gettign a bigger RR brake setup out back PLUS the issues with the existing 4wheel Kits Brake bias and Ft/Rr Brake balance are to be considered.

from what i hear even with Stoptech's claim that they make specific changes to the rear setup o nthe 4wheel IS 300 kit to balance the brake power front & rear there is STILL an issue & two owners of their 4 wheel upgrade kits have not been happy with the brake bias..... Still TOO strong out back.... very easy to lock up/ No modulation.....


here are a few pics of my new 14 in Front Stoptech setup and my OEM sized rears.




wassup Ed,
so what do you think of the front BBK and OEM sized rears? do you feel any brake bias that people have referred too. i am thinking about getting the Rotora 330mm 4 pot BBK for the front and i was planning on just getting slotted OEM sized rotors from Rotora for the rear. what do you think about that setup, very similar to yours except my BBK rotor size can still fit a 17" rim.

your car is looking sweet man
 

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GangusKhanh² said:
On the same note, Endless, StopTech, and AP Racing also make 4 wheel BBKs for the IS.
Rear BBK: Stop tech = yes, AP = maybe, Endless = no. (<=i'm sure of this one, lol).
 

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i believe Stoptech & Rotora are the only ones that currently offer an AVAILABLE, & in production 4 wheel BBK upgrade for the IS .


i am still evaluating these brakes now... i beileve that more power out back could be a benefit on a track with more agressive front pads... but for the occasional track days & the canyon runs i like plus the daily driving.. i think an OEM sized rear is fine.... i am runing Axxis pads out back that have a bit more bite than the ceramics i had in front on the LMW brakes, These Stop techs also have the low dust (harder) pad option.... so i think that with a less grabby front pad and a nice grabby rear i have a pretty decent setup for balanced brakes- given the differences in the sizes !! ;) ...it might be different if i put a more agressive front pad or track compound pads for track days..... then i might see a reason to look at upgrading the rears for a reason other than for show.

as i see it & for daily driving the bbk front OEM drilled or Drilled/ slotted rears is pretty much perfect for all conditions.

i really think the 4 wheel BBK setup is REALLY a big "SHOWPOINTS" mod MUCH more "Form over Function" ....and i agree it looks SOO bitchen to have a badass set of wheels & A KILLER 4 wheel BBK setup..... i'd just rather spend that cash elsewhere right now....

i think i drive pretty agressively when it is safe to do so and i am so far good to go on these brakes as is...:)
 

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edgy said:
from what i hear even with Stoptech's claim that they make specific changes to the rear setup o nthe 4wheel IS 300 kit to balance the brake power front & rear there is STILL an issue & two owners of their 4 wheel upgrade kits have not been happy with the brake bias..... Still TOO strong out back.... very easy to lock up/ No modulation.....
Have those two owners triedto contact us to try to solve the problem?

All of our kits are balanced to stock rear brakes. We do this by giving specific piston sizing for each platform. With larger piston sizing, more brake torque is outputted. Smaller pistons have less brake output. For proper brake torque to achieve the right brake balance, the right piston sizes must be chosen to be mated with a particular sized rotor since the larger the rotor, the more leverage is being applied and in the end, there is more brake torque. The front only 332 kit has a different front piston size than the front only 355 kit. The front 355 kit has different piston sizes from the front of a 4 wheel 355 kit. All of this is to obtain the right brake balance. If the front only 355 kit was put on a car with the rear of our 355 kit, the car would be too rear biased. Our 332 or 355 front only kit although has a larger rotor, does not shift bias towards the front of the car.

There is the possibility that the installers of the 3 wheel kit got the front and rear calipers mixed up where they put the front on th rears and the rears on the front. That would cause a very large inbalance.

Anytime you shift brake bias towards the rear it causes the car to become unstable under braking events. ABS usually covers for this, but in trailbraking events, the car can be outright dangerous because if the rear end locks up before the front axle, then the car will easily swap ends and create a bad oversteer event.
 

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THanks for posting this Stop tech.

excellent post response to this report/feedback...

I am not in a position to comment on the specifics of their individual brake setups or install etc... just reported the feedback i have heard from them when i asked how they liked their setup in the over al lquestion of a 4 wheel BBK setup & how it generally performs. as always a big part of the decision here for most is the value Vs performance issue... a select few will buy just to have...but more discerning spenders will want to be sure it will work best or better for them before before spending the Cash......

God only knows what the specific reason for their feelings are or whether some other issue is causing them to feel less than totally positive......

I will recommend they talk to you guys again...:)


Also.. . if i were to 1st properly identify my front 355 setup as a "Front Only" 355 setup.... this would not necessarily be compatible with an upgrade to a Rear BBK upgrade you offer as the Front 355 for a 4wheel BBK setup is slight ly different than a Front 355 for a Front Only correct...?

How would you accomodate this issue for example, SHOULD i decide and have the funds available, to upgrade the rear with your matching BBK as well..?


PS.. .I LOVE my STOPTECH 14 in. Front BBK!!!!!!


SIIICK Brakes!!!
 

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If you bought a front only kit new, you more than likely have a front only kit.

To upgrade to a 4 wheel kit you would have to have the front calipers replaced. You can either sell the kit as a whole and put that money towards a 4 wheel kit, or you can simply just get another set of front calipers with the rear kit. The problem with that options is that you would left with some calipers that won't fit many other applications.

Currently your brake setup is designed to be balanced with the stock rears. The rear kit needed a 355 rotor because of the size of the parking brake. The 355 and the smallest piston sizes in the 4 piston caliper make the rear brake torque go up. In order to keep the system balanced, the front calipers of the 4 wheel kit had to be made larger than those of the front only. This isn't to say that a 4 wheel kit will stop better than a 2 wheel kit. The pedal feel may get better, but in terms of stopping distance, there will not be a significant increase. Stopping distance is still very largely influnced by how sticky the tires are.
 

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i bought it used .. . .so that is why i cannoit be totally sure oif the "Spec" of this setup....

obviously you guys dont offer that SWEET Blue color option i did hehehehe


Thanks again for your post!!!


One Q.. . Will a 4 wheel front caliper set have a better/Different/More agressive 'bite' or feel Vs a Front only front set... ? due to the bigger pistons...?

& can this difference be mitigated by using different spec Pads Ft & Rear...?...

Example: I currently am using a ceramic Dust free front pad in this 355 setup....& i am also using the fairly agressive AXXIS 'Ultimate' pad out back on the OEM setup... the idea being that this might "balance" the brake feel a bit with SUCH a big badass front brake up front compared to the relatively tiny rear........help the rear get a bit more 'bite' to more evenly "match" the killer performance of the fronts even with the harder dust less, & less 'bitey' or 'grippy' front pads....?

Just a thought i have not had these brakes on for more tha n a week so i have nto had the Oppty to drive agressively yet & really test this theory out... My previous experience was with the Supra TT brake setup up front & then a custom engineered Lexus LS400 Caliper/Rotor front brake setup before the new Stoptechs...

thanks again


edg
 
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