<VV> ? what to use to model header pipes?

[BBRT]

Trying to find flexible hose, tubing, foam, or something I can model header pipes from heads to collectors. I want to make up various configurations and figure out the best curves, etc. for the equal length tubes to fit my particular cars. Ideally, the ~ 1 1/2" od material must hold its shape once bent and be re-bendable for re-use. Of course it needs to be inexpensive as I need to make up three at a time. Diameter and smoothness are not an issue.

I went to Home Depot and a big craft shop and didn't find anything I could use.

Any thoughts, ideas, sources, etc?

Chuck S