-CIS fuel line diameter sizing-

[koolkozak]

79 911 SC.

Need to replace lines coming from the fuel distributor (FD) out to various places. Ive been researching and found different answers about the sizing of the diameter of the lines. Can someone confirm what the proper inner diameter (ID) on the CIS lines should be? I would like to use the original polyamide lines or something comparable, not steel.

Ive seen people post that the ID of the line from the FD to the cylinder injectors are 4mm, ive also seen 3mm, 3.13mm and even 2mm(stainless steel braided lines) being reported. What is the real answer?
So
FD to cylinders --- 3mm??
FD to cold start valve --- 4mm??
FD to fuel filter --- 6mm??
FD to WUR --- 4mm??
FD to pressure relief valve --- ???

[koolkozak]

Nobody?

[E Sully]

Here is a link to my thread on the CIS fuel lines. CIS Fuel Lines
It is important to get the correct line or it can affect the fuel injectors if they are too light weight and flex during operation. The contact I used is Verell@unobtainiumsupply.com
He is very reliable and the quality of the lines is excellent. Get in touch and he will help you out

[koolkozak]

Yes i have read your post, and ive read others that post different sizes. For example the most frequent one I saw was that the line to the injectors are 4mm inner diameter instead of 3mm like your post states. So i see discrepancies. Who do I trust?

[boyt911sc]

I have several sets of OEM fuel lines for '78-'80 and '81-'83 SC's. I'll let you have one of them in order to prevent you from building your own fuel lines. These are critical fuel lines you could not afford to take a lot of risk. Or either contact Len (BoxsterGT) to have him make them for you. PM sent.

Tony

[koolkozak]

Thanks Tony, I am already getting a line from Len that i need. I just want to know the specs, which nobody seems to be sure about and cant find a clear answer.

Trying to learn as much as i can. And in case i need to replace other lines in the future. Porsche doesnt have these specs anywhere?

[koolkozak]

anyone?
I talked to Verell at Unobtanium, he only knows the ferrari specs for their K-Jetronic CIS.
Are the specs the same for my 79 911SC?

[timmy2]

din 73378 PA11WLT Tecalan-78 is what the larger line I have has for markings. No markings on my smaller tubing.

[koolkozak]

thanks but that doesnt tell me much. So nobody knows the size of the lines that are needed for replacement lines for our cars. Hmm