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Some weeks ago, I think, someone posted a pic identifying the vacuum hoses on a Bosch FI Spider engine and (I think) their sizes . . . maybe Tifosi. Does anyone have that pic and vacuum hose size info? Going to replace the rest of my vac hoses that have not already been replaced. Some are the original fabric wrapped hoses and I would feel better replacing them.
 

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hose size help?

I was wondering what size the hoses in the trunk were.
http://www.hiperformancestore.com/images/SpiderTrunkHoses.JPG

I am referring to the smaller pink size hose.

I measured 4mm, but I used a ruler not a calliper. Was wondering if anyone measured any differently, and I wouldn't want to buy the wrong size.

Note: i would buy the kit, but I already replace the other hoses that come in the same kit, and when I called, they wouldn't sell me only this hose...


2. On a curious note: what is the difference between vacuume hose fuel hose? I didn't notice any difference myself, but I'm assuming there is.
 

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I was wondering what size the hoses in the trunk were.
http://www.hiperformancestore.com/images/SpiderTrunkHoses.JPG

I am referring to the smaller pink size hose.

I measured 4mm, but I used a ruler not a calliper. Was wondering if anyone measured any differently, and I wouldn't want to buy the wrong size.

Note: i would buy the kit, but I already replace the other hoses that come in the same kit, and when I called, they wouldn't sell me only this hose...


2. On a curious note: what is the difference between vacuume hose fuel hose? I didn't notice any difference myself, but I'm assuming there is.
I feel the need to chime in here. Hey, those hoses are purple not pink! :)

Fuel line and vacuum line are totally different types of hoses. There are three big differences.

1. Fuel line is made from a substance that's resistant to gasoline and all the other chemicals commonly added to gasoline. Most vacuum line isn't and if used as fuel line will quickly degrade and damage the car's O2 sensor as bits of vacuum line get into the combustion chamber and then into the exhaust. Ultimately vacuum line will fail when used as fuel line. It may take months, or even years, but it will fail eventually.

2. Fuel line is made to handle a certain amount of pressure. There are high pressure lines used on the high pressure side of the Spider's fuel system, and lower pressure lines used on the return side. Vacuum line doesn't have to meet those pressure standards. However in the case of our silicone hoses they can handle very high pressures, and they need to on forced induction applications, but that's another subject. They still CAN NOT be used as fuel line.

3. "Rip-stop" protection. Fuel hoses, as well as radiator and other large diameter coolant hoses are multi-layered hoses with a fabric of some type in between. Most people think this mulit-layered approach is an effort to get hoses to handle more pressure. That's just a side benefit. Many single layer hoses can handle over 100psi, so it's not really an issue. What this does is makes sure that a tear/split on the hose can't go all the way through. If a fitting develops corrosion and vibrations starts a cut it will stop spreading when it reaches the next layer. This prevents a sudden and total catastrophic failure in while fuel starts spraying everywhere. In this case the hose will develop a slow leak, but it won't just totally fail all of the sudden.

I hope that clears that up. Vacuum hose, and certainly silicone vacuum hose can NEVER be used as fuel line.

On another note, we certainly do sell hoses separately. It's just that we have minimum order quantities when selling hose by the foot. We do that in lieu of having some sort of "handling" charge. I think that's a fair way to do it.

Greg,
Silicone Hose Kits
 

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I just called Spider

and Misty answered. She said she didn't know the size of the hose, and therefore couldn't help.
I know its either 4 or 5mm, I just don't know which.


If you were wondering, I have two other hose kits being shipped tommorow, I just wanted to buy that one extra hose and have it shipped with the rest of the stuff.
 
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