maximum temp under intake? vac hose q
 

I just bought an FD and one of the first things that I'm going to do is replace the vacuum lines. Silicone seems to be the material of choise BUT it doesn't have very good resistance to oil. I don't want to have to replace the lines a second time because the oil that goes through the intake broke down the silicon.

The alternatives that I'm looking are

1: Buna-n (nitrile) its max temp is 212 degrees but it has very high resistance to oils. Its also only about 50 cents a foot.

2: Viton. Its max temp is 400 degrees and also is chemical resistant. This would be my number 1 choise except for the cost. Its about 3 bux a foot.

Can I get away with the nitrile tubing (low max temp) or should I go with silicon and risk having to replace it all down the road cause oil caused its death?

if you guys wanna see where I'm looking at this its at www.mcmaster.com , you'll have to search for 'tubing' ...or be more specific and it will come up.

garfinkle uses buna-n with no problems he also flars the metal tubing ends and uses tie wraps . viton was priced to us for $7 per foot

use the viton tubing, you can get it from McMaster's for $2.40 to $2.91 a foot. Get the 60 durometer.

Here's the link (at the bottom):

http://www.mcmaster.com/pdf/106/0075.pdf

Also, with the viton, you really don't need clamps except for a couple of hoses.

Using my PFC as a temp gauge I regularly hit 212F. Then when you shut the car off, it continues to get hot. This is called heat soak, sometimes when I restart, like say at a gas station, the PFC will read 108C until I get moving, then drops to 89C. So imagine those 212 max hoses heat soaking after every run. It may be ok, but I would get an ulcer worrying about it all the time, especially if you're the type to get worried about oil in the intake hoses breaking them down. Peace of mind ain't cheap.

I was looking more into this and the wall thinkness for their silicone rubber hose 2mm and the viton is 1mm think. I don't want this to collapse under vaccuum. Viton is 'firmer' though.. Has anyone actually used the viton tubing?

I did my hoses with Viton. You must use the much more expensive hose with 1/8" walls to prevent kinking (not the cheap version mentioned in the message above). The hose is very good to work with (more rigid than silicone though). I found that you can replace the existing preformed lines to exact length with this tubing without problems. I bought 25ft of 1/8" and 10ft 1/4" and had tube to spare.
-MP