Valvetrain noise after tune and dyno Ls 4.8
12-17-2018, 04:50 PM
#23
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Ok so here’s the data. Used pushrod measure 7.385-7.39 even the bent ones. Using my pushrod checker which only would go down to 7.37 at zero lash took just short of one whole turn to seat the rocker. So by my math that’s just about right with .050 preload.
That means a 7.375 pushrod would be what I want. I think comp does them in.025 increments. Or should I just go back with a 7.4? But that would be close to .075 preload.
The interesting thing is that I thought that I would see more length difference in the bent rods that would be causing the valvetrain noise I have.
That means a 7.375 pushrod would be what I want. I think comp does them in.025 increments. Or should I just go back with a 7.4? But that would be close to .075 preload.
The interesting thing is that I thought that I would see more length difference in the bent rods that would be causing the valvetrain noise I have.
https://ls1tech.com/forums/generatio...r-preload.html
12-17-2018, 07:34 PM
#24
TECH Senior Member
If they are bent, replace them with larger dia/thicker wall pushrods. ONLY straight PR's allowed....
12-17-2018, 07:39 PM
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12-18-2018, 09:18 PM
#26
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Do you have stock rocker arms and if so have you done anything to them? Also how much lift is on your cam? Pushrods sound like they may be the culprit but it could also be dirty/worn out lifters.