How close is too close

[Gjac]

Someone posted awhile back about brake lines being too close to the exhaust manifolds causing the fluid too boil on long grades and loss of brakes so I went under mine and looked and found mine were about 1 1/2 ins away from my headers. I also noticed that two lines from the trans to the cooler were only 1/2 in away from the header. I wrapped the brake line with FG cloth because it was easy to do. The trans line would be much more difficult. So my question to those that have added headers to a 454 TBI(Thorley) have you run into this issue and have rerouted the trans lines or is 1/2 in clearance enough not to heat up the lines?

[the_bear_II]

The Thorley headers on my 454 caused several problems at first.

>Melted the casing on the speedo cable. It ran above the headers over to the transmission. I finally found some high heat resistant heater hose, that I cut open and covered the new speedo cable with.
> Never lost brakes but they got spongy so I covered the brake lines near the headers with fiberglas cloth.
> Melted the power cables at the starter eventhough there was a heat shield. I installed new cables and wrapped them with the heater hose. Over time (about 2 years) it got brittle so I had to replace it.
> Burnt spark plug wires. I tried a couple of sets but nothing worked until I bought a set with ceramic ends for the spark plug caps.

At the time we were going up several different 6 to 10% grades in 80 degree heat. Most of the grades were under 10 miles long but he worst one was 21 miles long. I was in first gear at 15 to 22 MPH, squirrels ran along side so we could feed them peanuts...just kidding.

[jfkmk]

The boiling point of brake fluid is more than 400f. The issue is brake fluid absorbs moisture, lowering the boiling point. I wouldn't reroute brake lines (the engineers know what they're doing when they design these things) but I would change the brake fluid every 3 years.