If you are refering to an injector line, I have no idea what hose to use - those lines would need to be rated for more than 2000 psi.
If you are talking about the low pressure lines from the tank to the injection pump, I am using Gates Barricade carburetion hose. The Barricade carburetion line of hose is rated for 50 psi working pressure with DIESEL, BIODIESEL, gasoline, ethanol, gas/eth blends including E85, and 100% methanol. Temp rated with diesel/biodiesel for -40 F to 212 F.
The Gates Barricade fuel injection hose is similar to the carburetion hose but is rated for 225 psi working pressure.
Regular gas hose will work, but diesel and especially biodiesel will eat it much quicker than the Barricade hose.
At my local parts store, regular Gates gas hose 3/8" costs ~ $1.25 per foot. The Gates Barricade carburetion hose in 3/8" costs about $1.90 per foot. Not much difference for a much better hose. The fuel injection hose jumps to about $4 to 5 per foot.
The Barricade hose is also CARB approved.
The Gates part numbers for the carburetion hose on a 25' spool pack (what most parts stores around here keep on the shelf and sell be the foot) are:
3/16" 27312
1/4" 27313
5/16" 27314
3/8" 27315
1/2" 27316
http://www.gates.com/downloads/BarricadeBrochure.pdf
Hope this helps,
Ronnie
