Hot Rods Usable Material for Spark Plug Wires Conduit?

The look of the top end of the 4-cylinder DOHC engine going in my '28 has to be pretty traditional; after all, it is a focal point of this car.
I'm using braided spark plug wires, and I like to enclose them in a conduit, distributor-to-spark plug, as many prewar cars did (heck, Henry used TWO of them on the '32 4-banger's optional engine...)
Most material I've read sez to keep the spark plug wires at least 1/2" from each other (arcing) and metal parts (arcing and grounding).
I think this conduit is going to wind up a simple straight length, from the distributor mounted on rear of exhaust cam housing to plug #1, around 16-18" long. This conduit may have a tight 90-degree elbow at the dizzy end; depends on how tight I can get the bend and how lazy I am at that point...
1" tube OD measures out right for 8mm wire.
With no metal contact in mind, from what materials can I build this conduit? I've been thinking Schedule 40 CPVC:
Pros: non-metallic, tight-bendable, CHEEP, but...PVC? Really?
Cons: CPVC may-or-may not stand up to engine heat and definitely wouldn't stand up to the post-powder-coat oven, but...PVC? Really?
How well does CPVC hold sprayed-on paint?
Other suggestions?
Eddie

 

The PVC won't like the engine heat at all; it will sag sooner or later. I used to bend PVC when I didn't have the heat blanket on the job by sticking it over the exhaust pipe on the shop van and running the motor at about 2K RPM for 30 minutes or so. If the motor is fully exposed (no hood top or sides) you might get away with it, but in the Texas heat I doubt it.

If the plug wires are modern wires with just a braided cover, running them inside a metal tube should be acceptable.

 

Could you use a metal tube and a thin plastic type liner?

 

look at brillman.com and search under conduit

 

I'm sure stainless steel, steel, copper even aluminum has been used, try it if it doesn't work try something else.

 

Black heater hose used on both sides of my 21-studder. Have to look close to see that they're not the steel tubes.

 

Gentlemen, good answers all--WELL DONE!
Heater hose, indeed! (I likes it).
Other subjects: Fryday night, and the 3 Frogs are croaking...loudly...
Eddie

 

On my flattie I used 2 x hardwood ,routed out halves on each piece .use a cad to get them exact .If you keep the total thickness to 3/4 inch ,trim em up nicely and I painted mine satin black . look snazzy and will take any amount of heat ,short of a fire .

 

Yeah, wires should be spaced 1/2 inch apart but there's plenty of engines with wires bundled together and laying on metal engine parts or in metal conduit..It all depends on the quality of wires and spark energy..

 

Ultimately back in the day if it were a factory thing, I would say bakelite.
If you wanted to recreate that look on the cheap, use MDF and route channels in a pair of halves and paint it dark brown.
Else, cast epoxy tinted with dark brown and sienna, mixed loosely.

Phil

 

Could you use the flexible line from a shower head. It is Teflon lined and can handle hot water.

 

I have seen copper tubing used, with each end flared, solder the four tubes together, and then chrome plated.