98camZ

iTrader: (3)

i just installed a a custom ground cam from comp cams with a 588 598 112lsa and i ordered 7.425s for rod and i got a ticking noise from the valve covers just wondering if it is the wrong size of pushrod maybe i need to go to 7.400 stock length. I called local tuning shop and he said he always goes with 7.400 rods, maybe i need to let it warm up a bit and wait for the oil to get up there would that hurt anything. I have a pushrod length checker but have no clue how to use it anyone give me some tips are advice on what i should do......

98camZ

iTrader: (3)

6.800+11x.050=7.350 is what i got when i checked it with the pushrod length checker!!!

DaddySS

Check several intake and exhausts with the checker and use your best average. .080 to .100 is what is recommended for a quiet setup so the 7400s would be better based on that one measurement.

98camZ

iTrader: (3)

ya i see now why i had ticking goin on the 7.425 is to long and i got 7.400 coming tom sucks tho that i gota change them all out tho

vettenuts

iTrader: (4)

If that is a zero lash measurement, 7.350 + 0.075" preload = 7.425" pushrod. You should be fine. How did you obtain that measurement?

2002 SS HUGG

I think you shouldn't have to change the pushrod length if you are using stock rockers and stock lifters. See, all you are changing is the lift and duration of the cam...which I don't believe will effect your pushrod length. See, I am about to install LS7 lifters and Harland Sharp 1.7 non-adjustable rockers. The point of this is that I found out that the LS7 lifters are a little longer than stock ones, affecting the legnth of the pushrod. As well, I don't know how the Harland Sharps will sit on the springs and what not. This is why I have ordered two sets of chromeoly pushrods 7.4 and 7.35 along with a pushord length checker so I do the change correctly and use the right length pushrod. If I find that I need the 7.35's I will gladly GIVE you my chromeoly 7.4's from TSP.

PREDATOR-Z

Are you on stock LS1 lifters?
How did you install rockers?
Are your springs at proper height?

As per your measurement 7.425s seem about perfect on LS1 lifters, unless there is something else we do not know.

98camZ

iTrader: (3)

yes i am on stock ls1 lifters and torqed my rockers down to 22 ft lbs and yes my springs are at proper height. but they still tick coming from the valve cover sounds like, so i didnt even let it warm up maybe for 1-2 min ran and i shut it off thinking something was wrong

98camZ

iTrader: (3)

is this normal noise because of the high ramp rate on the cam, ive watched a lot of videos on youtube of the ticking and ppl said it is normal after a cam install

vettenuts

iTrader: (4)

Are you saying the noise was immediately after a cam swap? It took several minutes for mine to quiet down after the swap so it may be the lifters just haven't pumped up yet.

98camZ

iTrader: (3)

the temp got up to operating temp and good oil pressure, when its running it sounds like a cold diesel!!! thats the best i can describe it

PREDATOR-Z

When you installed the rockers did you just trq all at 22ft/lbs and that is it or did you do the base circle on TDC following firing sequence?
See if you do not do proper install some of your rockers can be loose. When rocker is tightened on base circle, that is the smallest lobe area. If the rocker is tightened on another area of cam ramp it will be loose once reaching base circle and can have that ticking noise

willyfastz

If you measured right here, the 7.350 pushrods will be the right choice. No need to have .100" or more preload on your lifters .050 will be just fine or actually better.

PREDATOR-Z

*****, he measured 7.350 to 0 lash, so + .050 = 7.400 (if he did it correctly)

98camZ

iTrader: (3)

cuz i got 7.4s coming tuesday so i was gone try them and see if it got queiter

willyfastz

My bad, I don't do all the count turns stuff. Best way is to get zero lash and MEASURE the pushrod checker.

98camZ

iTrader: (3)

how do u do that

slayerized6

iTrader: (12)

taken from the cam guide sticky on the interneal engine section:

How To Verify Proper Valve Train Geometry
from Holly.com

The following is a method of verifying proper valve train geometry. After you have estimated the required pushrod length using a Pushrod Length Checker, use this method to verify that the valve train geometry is correct (using the rockers you are using in your engine):

1
The first step is to install a solid lifter and an adjustable pushrod. Mark the tip of the valve with a marker



2
Install your rocker arm and set it up with zero lash.



3
Rotate the crankshaft clockwise several times. Remove the rocker arm. The contact pattern of the rocker tip will be where the marker has been wiped away from the valve tip. The pattern should be centered on the valve tip, and as narrow as possible. If it is not, experiment with varying the pushrod length to yield the best pattern.



4
Pushrod Too Long: Notice how the pattern is wide, and shifted to the exhaust side of the valve tip.



5
Pushrod Too Short: Notice how the pattern is wide, and shifted to the intake side of the valve tip.



6
Pushrod Length Correct: Notice how the pattern is narrow and is centered on the valve tip.

PREDATOR-Z

That is incorrect for non adjustable LS rockers. P-rod length mainly adjusts preload on lifters, shimming the rocker stand adjusts wipe pattern on valve tip.

98camZ

iTrader: (3)

so why dont anyone say go with 7.4s and ull be fine