CDD injection line issues

IDIBRONCO

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You can buy a large o ring to seal it. I think that you can use the sealing gasket for a Holley 4bbl carb to seal it too.
 

ROCK HARVEY

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Well I did some measuring just now, and the results are disappointing. I measured the lengths of the injection lines by pushing some 80lb test fishing line through the lines to get an accurate internal length. The new #1 line and the old #1 line were both the same length at 17.25 inches long. Initially I thought that just meant I needed to re-install the timing adapter. But then I measured some more lines, both old and new.

The original lines (except #1) were 18 and 5/8” long, but the new ones are 19.25” long. So they kept #1 the same but added 5/8” to all the other lines with this new set. In order for them to all be the same length the timing adapter would have to be 2” long, which it is not.

Long story short I do not recommend this line set to anybody as it will cause timing problems. The#1 line is the only one that’s the same length as the original lines, so if you need any lines besides that I would try to find a good used set. I can’t believe CDD didn’t check this when they received them from the manufacturer.
 

Nero

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You should call em up and see what they have to say about it
 

ROCK HARVEY

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I sent them an email this morning telling them my measurements and asking whether I got a bad set or whether they are all this way. In the meantime I re-installed my old lines except for #1 since it was the correct length in the new set and my old one was messed up. This has been a major pain, especially since I bought from a reputable company specifically to avoid these types of issues. I’ll keep you all updated with any replies from CDD.
 

jwsfarrier

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Thanks for doing the research on this. I have a set sitting around I haven't installed yet. I will be curious to see what CDD has to say.
 

MasterBruh

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Did they every get back to you about the line lengths? What did you end up doing? My #2 line gave out and drips fuel about a drop/s so I was going to buy this set, as CDD is pretty reputable, but after coming across this post I am back to the drawing board...
 

Clb

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Sounds like the answer is not what we want to hear....
 

DirtyWood

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Did they every get back to you about the line lengths? What did you end up doing? My #2 line gave out and drips fuel about a drop/s so I was going to buy this set, as CDD is pretty reputable, but after coming across this post I am back to the drawing board...
If you do get the whole set of lines you should be aware that more than a couple people have had difficulty timing the injection pump due to erratic RPM readings becasue the aftermarket lines are not quite the same as OEM . I replaced the #1 line and I'll get a good RPM value at idle but as I increase RPM it starts to read erratically. At least keep the original #1 and #4 lines even if just for timing purposes. My .02
 

MasterBruh

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I could be wrong but if the CDD lines are longer than the original, wouldn't that mean that mixing old and new lines could cause timing issues due the varying lengths?
 

Clb

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Pop timing yes, but the actual #1 or #4 timing sets the ip event.
So as I understand it, basically yes...
Time and distance is directly related here....
 

ROCK HARVEY

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I did eventually hear back, and they asked me to mail the lines back to them so they could check them. Unfortunately by then I had already thrown them away, except for #1 which was installed on my truck.

I still like CDD as a company and have continued to do business with them, but if I needed a replacement set of lines I would definitely find a good used set. If you want to buy a mass-produced set, just know they are all the same Chinese stuff. I’ve seen a few places that can make their own custom lines, but they are big money.

Sorry I don’t have a definitive answer for you because I didn’t send the lines back to CDD. If anyone else has a set of their lines and is able to measure them like I did I’d be curious to know.
 

ROCK HARVEY

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I could be wrong but if the CDD lines are longer than the original, wouldn't that mean that mixing old and new lines could cause timing issues due the varying lengths?
The problem was that the #1 line in my set was the same as my original line, but the rest were all significantly longer than the old lines. That’s why I used the #1 line but not the rest.
 

Olds64

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Interesting thread. That's ingenious using fishing line to measure the length of the injection lines. I would be the one using an old shoe string and would end up with inaccurate measurements. :idiot:

Good to hear that CDD asked you to send the injection lines back. Too bad you already threw them away.
 
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MasterBruh

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I did eventually hear back, and they asked me to mail the lines back to them so they could check them. Unfortunately by then I had already thrown them away, except for #1 which was installed on my truck.

I still like CDD as a company and have continued to do business with them, but if I needed a replacement set of lines I would definitely find a good used set. If you want to buy a mass-produced set, just know they are all the same Chinese stuff. I’ve seen a few places that can make their own custom lines, but they are big money.

Sorry I don’t have a definitive answer for you because I didn’t send the lines back to CDD. If anyone else has a set of their lines and is able to measure them like I did I’d be curious to know.
I appreciate the detailed response. I had called them up last Friday and the gentleman on the phone was adamant that the lines might be longer, but it would still work if you changed the whole set. I still don't trust that, given what happened to you with the uneven lengths that would be true.

I think what I will do is go get some used lines as only one of mine has failed so far (and it's easy to remove by itself). If I were to buy the CDD lines, I think I would measure them the way you did to see if they actually are the same length.

I will also continue business with CDD as they are a very good company nonetheless (and they are from San Antonio like I am so I'm supporting locals). Again thank you for the thread Mr. Harvey :popcorn
 
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