My original brake lines from the master cylinder down to the pressure switch just below the master cylinder run down the inside length of the fender well toward the headlight and then back. Why the 3' of brake line when the connection is just below the MC?

When I changed my MC it was easy reconnecting the lines with all the wiggle room built into that length. I shudder to think how much fun I would have had if they came straight up along the curve of the fender. Length is good when it comes to things like this.
(';')

The originals have pin holes in them. I was going to replace with flexible steel braided. I'm trying to understand if they need to be that length for some reason.. Pressure or cooling..??

Having re-lined a few cars over the years I can tell you the shorter the line the more perfect the length and bends have to be so that it fits right. If the line is longer there is much more room for error. In the almost hand made way Jag's were assembled back then it's would have made sense to leave them long and bend them to fit to keep production moving.

Could be long for heat dissipation too. I wonder if the RHD drive car had the long lines too. There are no exhaust manifolds near the lines on a RHD so that would be a clue.

Found this picture...Looks like the routing is to ease assembly.

http://www.myjaguarstory.com/resourc...2010%20007.jpg

Thanks guys.. I will go with a similar length of braided just in case it needs to distance for cooling..

OMG that's a beautiful engine bay! I don't need to see pics like that...

Imho, I would use cunifer lines, very easy to work with, no corrosion etc... Standard fare on volvos, and others. I have them on three cars.

Domestic Nicopp Nickel Copper Brake Line | eBay


AGS 3 16 x 25' Nicopp Coil CNC 325 | eBay

These guys will make them up for you for easy money...
Austin Healey Wood restoration parts