Air line diameter

I am reworking an old truck with bad air lines. Is there any guidelines or literature that can tell me minimum line sizes for various components? This truck has had numerous hacks to it over the years and I cannot trust just replacing what is now present. I am using nylon hoses now but replacing rotted rubber.

Current list -

1. min diameter from compressor discharge hose (1/2in ID) back to the dryer. Was using 1/2 in ID rubber. Is Nylon ok for this application or should I stick with DOT approved rubber. My 2007 international uses rubber here and then starts with Nylon for everything behind the dryer.
2. min diameter from secondary (front axle) tank to foot valve. They have 1/2 in ID rubber now. Should I stick with the same or replace with either 5/8 or 3/4 Nylon.
3. Is 1/2 OD nylon OK for feeding from the dryer to the wet tank and then splitting the same to the primary and secondary tanks?

etc...

John

 

I have a 36 in braided 5/8 OD, 1/2 ID compressor discharge hose that I bought from Velvac to come off the compressor, then I switch to 1/2 in ID rubber air hose down to the dryer. From the dryer to the wet tank I went with 1/2 in OD Nylon. I think I should change that out to 5/8 OD Nylon given that the ID of the 1/2 is around 3/8 in. 5/8 ID is .445 in. Probably need more volume to feed the tanks. I went with 1/2 OD Nylon from the wet tank to each of the dry tanks thinking that the pressure is split between the incoming pressure and the dual outputs. However, if one of the tanks need to be replenished quickly, 1/2 may be restrictive - right? Maybe I should also go to 5/8 there?

Since I need to buy some 5/8 anyway I think I will run the front axle tank to foot valve in 5/8 also.

Thanks for all the help, guys!