How much do stainless brake lines matter with stock brakes?

[aoysgelt]

Did search could not find answer - please point me if there is existing discussion since I'd think it would be a common question...

On stock M3 with upgraded pads/fluid - how much difference would stock brake lines vs stainless steel lines make on occasional track use?

Thanks
Aleks

[tinman831]

Google pulls up quite a few threads on this. Answer is yes, you will notice a difference.

[lutfy]

Originally Posted by tinman831

Google pulls up quite a few threads on this. Answer is yes, you will notice a difference.

I would like to know how? Heard about the flex etc but HONESTLY who can really 'feel' it?

I did mine because the stock ones started to seep by the caliper connection and replaced it with BW. Did I feel the difference, not at all.

Lutfy

[Groundpilot]

Originally Posted by aoysgelt

Did search could not find answer - please point me if there is existing discussion since I'd think it would be a common question...

On stock M3 with upgraded pads/fluid - how much difference would stock brake lines vs stainless steel lines make on occasional track use?

Thanks
Aleks

The answer is no. Because they dont make a difference for what they are designed to do. Leave stock lines on, unless they are old and its time to replace them.

[808MGuy]

I could only feel the difference at threshold braking. Under normal use, no difference.

[Petros]

the difference is very subtle and hard to notice. But there is a difference. More importantly though, the steel braiding is also an armor to protect the softer rubber lines on the track. It's easy to nick a rubber line if for example you spin out and kick up some debris or whatever. So the braided lines are not only for better feel but also for improved safety as well.

[M3 Esq]

I just changed to braided lines on my 335i and I can feel the difference. After 3 track days I felt like the pedal felt a little soft under hard braking so I changed the lines and fluid. I was out last weekend and the pedal definitly felt more firm.

[Richbot]

Originally Posted by M3 Esq

I just changed to braided lines on my 335i and I can feel the difference. After 3 track days I felt like the pedal felt a little soft under hard braking so I changed the lines and fluid. I was out last weekend and the pedal definitly felt more firm.

Because you cooked the fluid and bled the brakes most likely.

I would run stock rubber lines with my stoptechs if I could. Cut a stock line in two sometime there is a lot more going on than just rubber. I will believe they are superior right after we start running stainless braided tires or someone shows me some data showing there is less pressure drop across less than a foot of hose in stainless jacketed lines, or explains why i should run them despite the fact I have seen numerous stainless braided lines fail due to manufacturing defects but not once seen a rubber line fail even when severely aged, though of course it does happen the sample size is infinitely larger with the stock style lines.

IMO these have caught on because they are cheap shiny and based on improving "feel" which is easy to sell when the purchaser has confirmation bias.