a little off the original topic, but has anyone upgraded the brake lines, fluid, and pads? i'm looking into doing this and found a kit from Stoptech-Stage 1. i don't know the stock setup specs, and am wondering if this would work. anybody been here?
I went with stainless steel lines picked up from Zeckhausen (I really don't work for them!) to give me a more firm pedal 'feel'. I believe they were StopTech brand. I like that firm response. It also really helps with heel-toe downshifting if you have a 6-speed, although I have a SMG and that's irrelevant.
Stock fluid is fine unless you track your car, in which case something like Motul 600 or other higher temperature fluids helps prevent boiling. The stock fluid is actually pretty good by street standards. If money isn't an issue and you want the best, put in Castrol SRF. To compare in liters, BMW is about $10 per liter (comes in 12oz bottles), Motul is about $30 per liter (comes in half liters), and Castrol SRF is about $80 per liter.
For pads, I don't know any option for the E60 M5 (stock calipers) besides the Pagid Yellow, which you do not want on the street. They squeal REALLY bad, but are a great track option (at $750 I might add).
Please post any information you have about this StopTech 'kit'.