[thstone]

Change the brake fluid, not the brake lines. Most likely you boiled your regular fluid when you "lost your brakes". A mushy brake pedal (or almost no pedal at all) is due to the air bubbles in the brake lines compressing as you push the brake pedal instead of the force being transmitted to the caliper. Changing to a fluid intended for racing will fix that.

Going to stainless steel brake lines will not do anything to keep the fluid from boiling, they just transmit pressure a teeny bit better than rubber brake lines.

I ran at the track all day on Sunday in 92F heat and didn't have any problems using racing fluid and stock rubber brake lines. Next track outing is three days at Laguna Seca at the end of the month.