Weight in it's pure form is not the issue. Rotational weight is more important though... 7lbs. of rotational mass is equal to 300lbs of dead weight. Give or take cuz I don't know the exact weight but it's very close to that. Thats why getting a lightened pulley and flywheels, etc. help so much.

Having said that, a lightened flywheel is worth more than a carbon fiber hood, in weight savings

 

I was talking to someone at a recent meet and he said that he wouldn't recommend them. I am not too sure why, but maybe someone that knows anything about the Racing Brake kit can enlighten us with more information.

 

I bought slotted StopTech BBK 3 years ago with Axxis Ultimates for street & HT10s for road racing. Also got stainless lines & Titanium backing plate ... I had called StopTech & asked about the Ti backing plates. They told me that the backing plates are only needed on heavy big power cars like 'vettes. I had just put the TurboXS stage 4 /w UTEC on the car & they weigh within 40 lbs. of 'vettes ... so I bought the backing plates.

In my opinion ... BBKs are *necessary* when you expect to be doing heavy braking from high speed repeatedly like on road raceways. The 1st or even the 2nd hard brake don't really have that much difference from the OEM brakes. BUT, the 3rd and more will make a tremendous difference with brake fade. Big rotors dissapate heat much better.

This only works when matched with the appropriate pads. My very 1st track experience was run with the Axxis Ultimates ... cooked them. Never expected that a noob could do that, but we pay for our education don't we?

So .... ppl get all worried about upgrading your HP w/o upgrading the brakes. I don't think that they are necessarily connected. Lets face it, you can't even begin to drive on public roads like you can on road raceways, and be able to keep your drivers license.

Likewise, you don't need a TurboXS Stage 4 to burn up your brakes on the track.

Last, the front brakes do all the work & front rear balance is critical, check out the tech papers StopTech. So you may not really need a rear upgrade, although I did. Same goes for "turning rotors" ... it is all about bedding in the pads & rotors.

But then ... BBKs look really nice behind and open spoke wheel .. so all of the above may not make much difference!!!

 

I upgraded the brakes on my '04 STi for Daily Driving and occasional track days, and I went with the following from Project Mu:

>Slotted & Dimpled 2-Piece front rotors on the front
>Slotted & Dimpled 1-Piece front rotors on the back
>First Set: Titan KAI Pads front and back (discontinued)
>Second Set: Level Max 900 Pads front and back (suggested replacement for Titan KAI)
>Stainless Braided Lines covered with Teflon sleeve

I purchased all of the Project Mu parts from Alex @ www.bozzperformance.com , and he has taken great care of me supplying these parts.

>I used AP Racing 551 Brake Fluid, which is suitable for mixed street and track use - http://www.apracing.com/car/brakeflu...sp?code=CP7551

I have had great success with the the above brake upgrades (to a vehicle that already has bigger calipers than a WRX), and I really don't think that I would have enough braking performance or brake fade endurance without it.

I definately would recommend a proper BBK (Brembo - Aftermarket or STi Take-offs, Stop-Tech) with some high-quality pads and rotors, stainless braided lines and fluid, to anyone with a WRX with 275bhp or above, and as PsiStar said, remember that our vehicles have considerable weight!