Technical Heat Sheild Material and Brake lines

I'm going to make some type of heat shield for my brake lines, bolt it to the lower two bolts under the master cylinder, to help the foreseen issue.
My thoughts are to loop tight under master, back to inside firewall recess, then down, seems the "coolest" routing option.
I have aluminum and stainless, stainless is thicker than the aluminum, which is better for the intended purpose ?

 

Aluminum: https://www.metalsupermarkets.com/which-metals-conduct-heat-best/

 

All the OE stuff is aluminum.

 

If it were me I would run those lines up and over to the firewall as fast as possible rather than any where near those headers and throw in a couple of loops that would be right along side the M/C. See technical drawing #1.

I would likely build the heat shield from aluminum (shiny on the outside) and use a phenolic layer inside (for heat protection). Go around the bottom and up the left side protecting and hiding the loops. See tech drawing #2

 

I agree with Bandit Billy on the placement

Aluminum for sure

You could also build two identical panels and bolt them together with 1/4” spacers in between to give extra heat distribution and protection with the second panel.

Or, a master cylinder with the ports on the other side and run them down the tunnel avoiding the headers all together.

 

Both great ideas

 

I have a little tab of stainless between my # 1 header tube and my alternator. Seems to do it's job.

Gary

 

For designing a heat shield, it is not thermal conductivity you're looking for. What you want is low emissivity, since you're trying to block radiative heat transfer. Here's a nice chart:
https://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html

Polished aluminum has one of the lowest numbers out there. Bear in mind, once it's dirty or oxidized its effectiveness is greatly reduced.

 

The commercial stuff the go-fast boys put around their turbos is a woven sandwich type aluminium sheet, it can be worked and bent just like ordinary sheetmetal, and is very thin.

 

Here is what I did to cool off my new dual master cylinder on my 56 Thunderbird.

 

Why not just slice some 3/8" rubber hose lengthwise and cover the brake line closest to the exhaust with it?
Zip ties can hold it in place if needed.

Rubber is a far better insulator (lower thermal conductivity) than aluminum or stainless steel.

 

Another option - I got some stuff from Summit Racing that's an insulated sleeve made to fit over tubing or wiring. Not sure who makes it or what it's called - heat sleeve maybe? Comes in several sizes and lengths. I used it on transmission cooler lines. Might do the trick if you use it on the brake lines.

 

^^^^^ I used this where my fuel line runs by the exhaust from my rams horn manifold on my '36.

Gary

 

My headers are really tight to the firewall so there's only a couple of spots to feed in there.
I mocked up a couple different routes, the loop under the master and over to the recess didn't look the greatest and is pretty close to the borgeson joint on the steeringshaft, this is the other which looks better.



The trade off is the lines within a couple inches of one tube or under the master absorbing heat off all the tubes.
I do have some of that heat shield from DEI I think that I could put around the lines but I think it'll need something in addition to it.

 

I understand what the OP is thinking but the MC is still out there absorbing what it can. The loops in pic would make for some interesting brake bleeding. If that concerned run the lines behind the firewall in between typical interior insulation.

 

You beat me to it. Polished stainless is close, and should hold its shine for much longer.

 

Your headers look like mine. I whipped up an aluminum shield and put heat blanket on the underside. No issues.

 

Asbestos still works the best!

 

I personally avoid running any lines higher than the outlets on the master as it can often make bleeding the system troublesome. I would indeed get the lines pointed back to the firewall directly, just not up higher first.
I always use aluminum as it shields as well as anything, but dissipates heat faster.

 

I would make a double walled heat shield for the master (with about 1/2" space between the sheets of 3/16" aluminum), then run the lines into the inside the firewall wrapped in the DEI heat sheath and pop back out at the bottom of the firewall (routing them to the left side away from your feet as much as possible.

 

I would start the engine, get it good and hot, then check with an infrared heat gun, the engine compartment looks well ventilated.You may not need anything. Looks like a good 4-5” from the m/c. Route the brake lines above the old master bottom bolts.

 

I don't think the brake lines or master cylinder are going to be an issue as brake fluid is stable at temps way beyond anything you will get that far from the headers.

Having said that the issue could be firewall behind the headers. That will get hot from the radiated heat off the headers. I would seriously consider using stick on gold heat reflective material to stop the heat getting in the cab.

 

You can even rest a beer on it... win... win...

 

The asbestos panels on the firewall of the Healey I worked on site did the trick. Wouldn't hesitate to use them again.

 

So this is how I routed them and I think I'll use the stainless as the shield and bolt the proportioning valve to it.

 

Thats tidy!

 

Looks great! The coated headers should be enough to keep the heat away... makes a big difference

 

https://www.thermotec.com/product/thermo-sleeve-2000-degree-f-slip-thermo-tec

I've used this on my fuel line and brake lines that are in "questionable" proximity to heat sources.

 

For anyone reading this in the future, use the highest dry boiling point brake fluid that you can. Wilwood 660, torque rt700, Castrol etc. it's expensive but we care about it old cars right?

Don't use any of that $10 Valvoline crap.

 

Cut your hard lines along the frame rail somewhere , and use a joiner.
Get some [one] braided brake hose made with a banjo fitting at one end [and banjo bolt into the M/C]
Run the brake line down the firewall with the banjo orientated rearward.
Fasten to the firewall with Cushion "P" clamps
Join the other end to the hard line.

I've seen this method used on numerous race cars.
It also allows for removal of the M/C from the firewall without needing to bleed afterwards