Harness DR25 Sheathing flexibility for bending

Hi everyone, I am building my first harness for a street car from a Haltech flying lead, this already includes the Fuse/Relay box ECU connectors etc and sheathed up to the firewall grommet.

I don’t really want to go down the route of concentrically twisting adding extra wires pulling apart what has already been done as supplied etc. Just want to complete the harness from the firewall out.

I will require 2x tight 90 deg bends and want to cover the harness with heat shrink like DR25.

My question is what will its flexibility be like for bending when not concentrically twisted?

What other options are there for these bends to reduce wire strain?

Am I better to use expanding braid? (didn’t really want to use this as I expect it will attract dirt/oil and become a mess over time).

You have two choices twist the wires (without doing the complete concentric thing your cable will not be perfectly round, but still more flexible if the wires are in a twist even if there are some overlaps). Or pre-form the 90 deg bend. When you run the wires sheath the first part, then actually bend each individual wire before sheathing the second part. You could use an adhesive lined heat shrink to "stiffen" this bend.

Thanks David both good ideas there.