Zero vibration on my lines they are pressure cracks splitting them long ways when I get over 3 grand mashing on it they split like a over cooked hot dog. I have had lines break from vibration and they always break around the perimeter in a circle. All my clamps are in place and lines are at rest when the clamps are put on nothing in a bind. I am going to try going to stainless lines as they break from now on I guess I don't know what else to do

 

I've had problems with conversion lines on my truck too. The worst ones were the .120 stainless lines I ran at first. After 2 sets, a few replacement lines and a $400 tow bill I switched to .093 mild steel lines. Just replaced my 4th .093 line in 30,000 miles. Planning on replacing the lines with a smaller set the next time I crack one. Have my lines supported with extra clamps and supports to the head too.

 

What injector are you running

 

110 hp lowered pop-off. ive been running those injectors for ablout 15,000 miles and just lost the first line with them last week. I thought i had the problem solved when I put those injectors in. Seem like the last injectors i ran put a really bad high frequency vibration into the lines where these injectors dont

 

Over-tightening will cause them to crack. Torque with crows foot to 25 foot pounds.