BBK vs. rebuilt Girling

[madman23]

I have a question I was hoping you could help me out with. I am looking to track and autox my car about 5 times in total this year. Right now I have Girling brakes and am wondering if there are any modifications you would do to the or would you recommend the street kit? The car is a 1988 325IX and I do drive it all year long including spirited driving in the snow. I need rotors and was not sure whether to go with slotted brakes and rebuild the caliper or a bbk which I wasn't sure if it was good for salt and snow.An info will help. Thanks

[kronus]

blank rotors, stock calipers, spend your money on nice pads.

I track an e30 on stock calipers and there's plenty of braking force. bigger brakes are generally reasonable if you expect issues due to a power bump, but kind of overkill otherwise.

[THMotorsports]

Skip the BBK unless you have plans to put down crazy power in the near future... I just did StopTech slotted rotors on my 325is, and some hawk ceramic pads. I also daily my car (in the winter as well) and so far i have loved the the difference.

[Cephas]

On ourtrack car my buddy and I run OP Parts rotors, stock calipers, and Performance Friction PFC08 compound pads. You will out-brake everyone on the track with that setup. It is recommended to have a set of street pads you can swap in as these are loud and DUSTY and may not be street legal.

I wouldn't do any slotted or cross drilled rotors. They actually will decrease your braking effectiveness (less braking surface area = less friction).

Be sure to either replace or rebuild those calipers (at this point replacement is easiest/not that expensive) and bleed all the old fluid out of your lines with fresh high quality DOT4 or better before you get on the track for the first time.

Having your brakes in exceptional order before you hit a track is the most important mechanical thing you can do, IMO. You would be amazed at the number of people who lose all brake hydraulics because they thought their 3 year old cars fluid didn't need to be changed out.

[madman23]

I just did a full bleed and put new fluid in there. Im going to order eveyrhting for the rebuild now. Thanks for all of the quick responses.

[SkiFree]

Kronus has got it.

THMotorsports: Stoptech rotors are just fancy plated/slotted Centric rotors (centric owns stoptech). You probably know this.

CEPHAS: If it is a dedicated autoX'er you drill the crap out of the rotor for the unsprung weight advantage. You're not racing them long enough to overheat. If it is a street car with slotted rotors the "lost surface area" is semantics for a forum debate, not a reasonable issue in practice.

[Cephas]

CEPHAS: If it is a dedicated autoX'er you drill the crap out of the rotor for the unsprung weight advantage. You're not racing them long enough to overheat. If it is a street car with slotted rotors the "lost surface area" is semantics for a forum debate, not a reasonable issue in practice.

From a pure autoX perspective, you are correct and that's a great point my track junkie mind didn't even think about.

He's going to be doing mixed driving between track and autoX though, so I'd say that my point remains. I have had several Brembo blanks crack on my track car - I wouldn't be willing to cross drill and thus weaken and reduce the surface area of the metal that slows my car from 100 mph as often as it has to.

A street car with slotted rotors is semantics for sure. Anyone driving a pure street car with slotted rotors (assuming they didn't come that way stock) is trying far too hard for style points. You will never heat the brakes enough to cause the fade that the slots are designed to mitigate. Seems that we agree here.

[Bimmerman325i]

A BBK does not fundamentally increase your braking power unless your stock system is in woeful shape. The point of a BBK is twofold: increase the amount of heat absorption and rejection the system can handle (i.e., repeatability), and improve brake modulation capability. Neither will dramatically alter how the car brakes, just provide better consistency and feel, at much higher consumable cost (and possible wheel fitment issues).

I really wouldn't bother unless you know exactly what you are getting from a BBK. My four wheel stoptech kit did not fundamentally change the braking power of my car, just improved the repeatability, consistency, feel, and the ability (and need) to better modulate the brakes. If stock brakes are a 7/10, the BBK would be a 7.5/10. It's not fundamentally different.

[madman23]

I wanted the BBK because the stopping power in my E36 M3 was SIGNIFICANTLY improved with my stoptech kit. It is a noticeable difference on the track and autox. I was hoping for that with my E30 which is why I was looking at them. I will be doing both HPDE and AutoX so I hope to feel a difference by rebuilding the factory brakes.

[TobyB]

If you're autocrossing, read the rules first. Slotted or drilled rotors may put you into a modified class.

For the track, rebuild and flush, and new hoses (your choice of rubber or teflon) and then
when you get to a certain point, ducts become important. Not at first, certainly.

Slotted rotors on the street are good for one thing- fording streams.
I bought a SET of slotted UltraRotors for $13 shipped, and other than the increased
noise and dust, they're excellent if you go driving through rivers-
your brakes work immediately, not 4 seconds later.

Otherwise, avoid Brembozo, as they seem to crack, and do try to find
non- Chinese stock rotors. Poland made good ones not that long ago.
Altho the Chinese are getting better quickly
(Centric, etc)

t

[iPee]

Plus one on the PFC-08

[pandaboo911]

Brakes don't really need to be upgraded unless you're increasing your horsepower and straight line speed. Stock e30 brakes are pretty good with a proper set of pads. You'll find some of the track pads will have so much bite you'll have to downgrade because the brakes lock up too easily.

Spend your money on a good ducting setup and pads. The braking force is handled by the tires. It's worthwhile to upgrade to some brass bushings and do a proper bleed as well.

Source: track miata with stock brakes. Only mods include ducts and racing pads. The brakes never fade, even 2 hours into a stint.

[e30_world]

Just doing my BBK now! Haha but I have a built S50 and ride it pretty hard. Stock calibers worked awesome till the track or super hard runs. If you get good pads, stainless and new fresh fluid, you'll be dandy! I'm upgrading to the RX7 turbo Calibers mostly because I'm poor and got a great deal on them.

[madman23]

So I am looking for a good for the street, track, and autox. Would you still go with the PFC-08 or Hawk HPS Streets? I also think I am going to do the booster delete as so far I have new calipers and rotors.

[stonea]

I just did new blank rotors, rebuilt calipers, Hawk HPS street pads, SS brake lines, and a 25 mm Master Cylinder. I love this set up, I don't track the car, but I do plan on doing some autox events with this set up.