Okay, after receiving this reply from Gunnar at Patriot Heads:

"The pushrod is probably correct, the source of the notice could be the valve springs. The heads come with the Patriot Gold springs. They sometimes have a tendency to cause a slight sewing machine sound because of them being dual springs and the greater seat pressures".

Now how many of you who have replied in the thread are running dual springs and if you are; do you have a louder sewing machine sound with them?
Thx

Sleeper

 

I have run both. Formerly, I was running Crane 832's. Now I am running PSI 1511 beehives. No perceptible difference in sound. Think you are fishing in the wrong pond.

 

Thanks vettenuts..just after receiving that info from Gunnar wondered had others noticed a differents..your input confirms it doesn't...

 

Two sets of duals.. no problem w/ noise. Some duals can keep it from being stock-quiet but it won't keep it far from it.


Arnel

 

Thanks Arnel,
Guess the only thing to do is wait for the PR checker to come in and use it to get the measurment for proper PR lenght. Question is; what if it comes up with an odd size can you have custom lenghts made?
Thx

 

Yes, but with the exception of Comp R lifters, the tolerance on preload is forgiving enough that a stocked length should be available. Also, Comp makes pushrods in 0.025" increments down to 7.300" and up to 7.500" for LSx applications.

Having said that, Smith Bros. makes pushrods with a true ball end rather than the formed end. In a prior post I suggested examining the rockers for contact. One way to alleviate contact issues if they exist is a true ball end on the rocker.

 

I checked the contact point of the push rods to the cup on the rockers and they are centered without going outside of the cup.
Do you have a LINK to Smith Bros. just incase I need to use them?
Thx,

Sleeper

 

www.pushrods.net

 

I am learning alot here! Thanks have had the same problem and will now us this to help do the work right!

 

Thanks vettenuts for the LINK

Well I also found on LS1 Tech some very interesting info on this subject.
I'm not the only one trying to figure out the problem and have gone to the sites to find the answer with the help of forum members.
You may be familiar with this thread..
http://ls1tech.com/forums/showthread...+maching+sound

Very good stuff here and it points out the importance of having the PR checker to get it right.

Sleeper

 

Got the Yella Terras today. Thanks Jason
now I got to get the lifters pumped back up because the car has been sitting to long and they have bled down.Correction they should be bled down.
Now waiting for the pr checker to come in on Thursday...hope I can have this running smooth by the weekend...

 

I think you want to leave them bled down when your checking pushrod length and preload.Correct me if I'm wrong anybody..................Paul

 

If they're bled down, it just make them more 'sensitive' and harder to determine when the free play is out of the assembly.

 

When getting the preload correct for Crane adjustable rockers, they want the lifters bled way down. Check out the link below and look past half-way down at the tech tips seciton.

http://www.cranecams.com/?show=newsLetters&no=148

Keep in mind the Crane rocker stud threading is much finer so pay no attention to the number of turns. It does not apply unless you run the same setup.

Arnel

 

My bad..yes they should be bleed down..thanks for advising me of the correction..

 

I'm easily confused...so are you saying DON'T bled them down? I believe I felt what you are discribing. On the bled down position I could feel the lifter give a tad before bottoming out.
Does this statement mean the same thing?
"Just be sure the rocker nut is only hand tightened and that you do not preload the lifter with the checker which isnt going to happen anyway if the lifter is already filled with oil. The lifter plunger is tough to push when the lifter is full of oil so it wont be easy to preload it, which is good."
The above is from LS1Tech
Thanks

 

The lifter plunger should be at the top, the question will be whether or not you can push it down by hand. If the lifter has bled down some, you need to be more sensitive to the feel of zero lash (hope your a sensitive guy ). Put the adjustable in a little short at first to see where you are at and then take it from there. I found I couldn't turn the adjustable with the Yella Terra rockers in place and had to remove them each time, tweak the pushrod length and then remount the rockers. So, just snug the rockers, don't go to the full 22 lb-ft each time it will be too hard on the aluminum threads since there is no heli-coil.

As a side note, the 7.500" pushrods showed up last night for 04BlueGoose's car. We set up a dial indicator and verified the preload at 0.100", which is right about where stock preload is from GM. It will hopefully make for a quiet valve train, however the lobes on his cam are very aggressive per the cam designer so we will see. When setup and the rockers were tightened, the initial preload was 0.050" due to the full lifter. However, you could watch the lifter bleed out as the valve spring forced the oil out and the needle on the dial indicator slowly crept up to 0.100" and stopped. The longer pushrods were necessary due to the shim used to obtain the proper wipe pattern on the rockers.

We are hoping for "Main Motor Start" tonight or tomorrow

 

I like...

 

Thanks again vettenuts for the input. That is a good tip on the aluminum threads...a friend had to heli-coil an couple of his threads after stripping them out.
Wish you luck on the "start up".
I hope this can be done w/o a dial indicator, because I don't have access to one. Also Yella Terras say trq to 25 Ft Lbs, so I guess that will work also for torquing.

sleeper........

 

[QUOTE=SleeperC5;1561707522Also Yella Terras say trq to 25 Ft Lbs........[/QUOTE]

I saw this, but their instructions are very generic and not specific to the LS1. I plan to stick with the GM number of 22 lb-ft, especially since we have bare aluminum threads in the head.