Shocking News: Stock E30 brakes aren't really up to S50 swap track use....

[nrubenstein]

I knew it wouldn't be great, but I will confess that I was kind of surprised by how quickly the rotors got trashed. This is after a whopping 15 minutes on track in two different sessions. I guess that super slow street tire apex speeds, lots of weight, and high straight line speeds will do that.

As a side note, though, it was great for the brake hydraulics. I can't count how many liters of fluid I've flushed through, but I got a ton of crap out of the system when I bled after the first session.

[Dave]

What pads, fluid, tires? And was this a fast track? What about cooling?

[gearheadE30]

holy cow...they were new before that 15 minutes? Also interested in pads and such.

[mr.vang]

i'm pretty sure its a 10+ years old rotor by the look of it

[nrubenstein]

i'm pretty sure its a 10+ years old rotor by the look of it

Two years old, looked pretty much new before then, aside from surface tinting.

[nrubenstein]

What pads, fluid, tires? And was this a fast track? What about cooling?

PF06es, Typ200, not ducted. In spite of the stupidly slow apex speeds, I was still getting close to an indicated 130 on correct diameter tires.

It's the DD, so I ran it in the time trial on a lark. If it ever sees the track again, it'll have ducts.

I need to take another picture - the surface looks better after some street driving, but the rust on the outside surfaces started flaking and peeling off after the next session.

[BlackbirdM3]

I'm not a big fan of Porterfield pads (I'm assuming thats who made your pads.) I've had fantastic luck with KFP pads. They have really good heat stability, and have a ceramic backing to help isolate the pads from the pistons. Their gold compound is the race compound but I run them on the street with no issues. The brakes are good, and get better as they get hot.

Brake ducting will go a long way for you. Higher end slotted rotors might also help.

Running out of brakes sucks. My first track day I ran into that issue, 3 laps and I had no brakes what so ever.

Will

[nrubenstein]

I'm not a big fan of Porterfield pads (I'm assuming thats who made your pads.) I've had fantastic luck with KFP pads. They have really good heat stability, and have a ceramic backing to help isolate the pads from the pistons. Their gold compound is the race compound but I run them on the street with no issues. The brakes are good, and get better as they get hot.

Brake ducting will go a long way for you. Higher end slotted rotors might also help.

Running out of brakes sucks. My first track day I ran into that issue, 3 laps and I had no brakes what so ever.

Will

Performance Friction pads. Aside from melting the rotors and using as much of the pad in a few minutes as a SpecE30 would in a mild season, braking performance was excellent.

I will confess that I had never even heard of KFP, but I am unlikely to switch from PFC. They wear like iron (unless you are literally vaporizing the rotors), and under reasonable circumstances, they are pretty easy on the rotors. I've used multiple Hawk and Carbotech pads on track and they were all shit. (Hawks didn't last and cracked the rotors, Carbotechs never seemed to be good for more than a weekend.)

[Ceeker]

number of factors I would think. Since the car goes considerably faster from stop to finish under such extreme conditions may not allow for cooling to be sufficient. You also have to consider quality of the rotors and pads and if you are getting adequate cooling to them.
cheap rotors might be ok for dd use. I wonder if you used oem rotors and pads would you get the same results? I have tech's who swear by using ONLY oem rotors and pads. you can take an M5 on the track with factory rotors and pads.

[jlevie]

While the stock brakes with PFC 06 pads are going to provide more than enough braking force, even for a S50/52 swapped car, they are going to be hurting w/respect to thermal management. Which is where a BBK will help (+ ducts for the front brakes).

[nrubenstein]

OEM pads would have been lucky to last two laps in this use. The rotors were just getting far too hot without airflow. Genuine BMW is not the answer. Cooling is the minimum solution and more rotor would be desirable for any kind of half serious use.

[Fidhle007]

I managed to overheat a Massive street kit with my S50 car and stock ducting...

[dude8383]

I managed to overheat a Massive street kit with my S50 car and stock ducting...

hehe, you're not the only one :)

http://www.r3vlimited.com/board/showthread.php?t=248323

I'm definitely going to be removing the backing plates/dust shields prior to my next visit to WGI.

[lcoleman]

Yeah, ditching the backing plates helped me tremendously. I suspect airflow is as important as rotor area.

[TobyB]

not ducted

well, there's one big problem...

t