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

[nrubenstein]

The stock set up is less than ideal. I am going to put some effort into the offseason to try and come up with a ducting system for the rear to try and reduce rotor temperatures to the more ideal 800-900F range.

Adjusting the bias may also play a little factor into this as well, since I have removed the ABS system but have not put a bias adjuster in. Brake performance seems to be more than adequate however, almost balanced perfectly. Thoughts?

Stock is biased heavily to the front and doesn't heat the back that way. I'd guess that removing the ABS shifted it. The thing is, though, that you want more rear bias in a track car. Stock bias assumes the kind of brake dive that you get on a stock suspended E30.

[bmnut2002]

The stock set up is less than ideal. I am going to put some effort into the offseason to try and come up with a ducting system for the rear to try and reduce rotor temperatures to the more ideal 800-900F range.

Adjusting the bias may also play a little factor into this as well, since I have removed the ABS system but have not put a bias adjuster in. Brake performance seems to be more than adequate however, almost balanced perfectly. Thoughts?

Bill, don't over think it, you don't need ducting on the rears.

[EtaSport]

Just had a session last friday at Summit point main. Tires I have are 225 toyo R1r. Stock rotors all around still with PFC 06, new rubber hoses and I just replaced all rear hardlines and flushed with ATE blue. I removed the front brake dust shields, no ducting.

I wasnt able to get the temps coming right off from the track. Best I got was after about 5 minutes after running fronts were still holding 280 degrees while the rear was around 340. 20 minute runs and I had to use brakes more often due to slower traffic but had no issues on front straight before turn 1. The average speed there was 135 with a best of 143.

I did notice some stress surface heat marks/light fracturing. I tend to get this every time but I have been using my rotors for awhile now so it's time to change. I'm thinking about the 280mm front upgrade now.