Proper Valve spring Height?
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From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Proper Valve spring Height?
Still having trouble adjusting my roller rockers w/o having them tick. I have done every procedure and I'm beginning to think my valve springs are at different heights which would cause this irregularity I seem to be having.
What is the proper way to check valve spring height?
What is the proper height for LT-4 springs?
Also wouldn't worn out lifters might be a culprit here? What would be a good replacement lifter for a hotcammed LT-1?
What is the proper way to check valve spring height?
What is the proper height for LT-4 springs?
Also wouldn't worn out lifters might be a culprit here? What would be a good replacement lifter for a hotcammed LT-1?
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From: O'Fallon Missouri
Valve springs do need to be installed at close to the same height. Also, there is a recommended installed height for each spring. I measured mine before I installed the springs. Put the retainers/locks on the valves, and measure the heigth from the seat to the bottom of the retainer. Mine were all shimmed within .010 of each other. I also installed them at the upper limit of the manufactures recommendation, for increased coil bind clearance.
What rockers are you running. My Comp Cams are nearly impossible to get completely quiet with the camshaft I am running. They still have that dull sewing machine sound at cruise. My previous rockers, Crane Gold, could be adjusted to quieter than stock. I just haven't been able to get the Comps that quiet.
What rockers are you running. My Comp Cams are nearly impossible to get completely quiet with the camshaft I am running. They still have that dull sewing machine sound at cruise. My previous rockers, Crane Gold, could be adjusted to quieter than stock. I just haven't been able to get the Comps that quiet.
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St. Jude Donor '03
I am running the GM Performance Parts 1.6 RRs out of the hotcam kit.
Also running the same springs out of the kit. I didn't think I would need to shim and all that jazz due to this being more or less the stock parts from the Lt-4. Probably was a mistake.
Any idea on good replacemnt lifters?
Also running the same springs out of the kit. I didn't think I would need to shim and all that jazz due to this being more or less the stock parts from the Lt-4. Probably was a mistake.
Any idea on good replacemnt lifters?
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From: O'Fallon Missouri
One of my first mods was roller rockers and LT4 springs. At the time I just dropped in the springs and drove the car for several thousand miles without a problem. But, now that I am running a much more agressive cam (224/230 605/622), proper installed height/seat pressure/ect becomes very critical.
You may be all right with your installed springs. Hopefully other running the same combination will chime in.
I would stick to the GM stock relacement lifters. Two of my good friends have had failures with the CompR lifters. One lost an engine because of the lifter failure.
You may be all right with your installed springs. Hopefully other running the same combination will chime in.
I would stick to the GM stock relacement lifters. Two of my good friends have had failures with the CompR lifters. One lost an engine because of the lifter failure.
Drifting
Joined: Feb 2002
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From: Little Rock Arkansas
You can check stem height with a straight edge if there's doubts about that. Unless you've installed longer valves in the motor or the seats have sunk you should be okay.
I'm betting pushrod length here... Pull a few of your rockers off on each side and clean the valve stem and roller tip with a degreaser; blacken the valve stem tip with a Sharpie marker and reinstall the rocker and lash it. Roll the motor over by hand (or with the starter) a few times and then pull the rockers back off and check your wear pattern on the stem. If it's too far to the rear your pushrods are too short; too far to the front they're too long. Wear pattern should be about 60/40 split rear to front (almost dead center). The tip should roll from just slightly off dead center at the rear to a little over center to the front. Your wear pattern will generally be about .090" or so in width.
-Jeb
I'm betting pushrod length here... Pull a few of your rockers off on each side and clean the valve stem and roller tip with a degreaser; blacken the valve stem tip with a Sharpie marker and reinstall the rocker and lash it. Roll the motor over by hand (or with the starter) a few times and then pull the rockers back off and check your wear pattern on the stem. If it's too far to the rear your pushrods are too short; too far to the front they're too long. Wear pattern should be about 60/40 split rear to front (almost dead center). The tip should roll from just slightly off dead center at the rear to a little over center to the front. Your wear pattern will generally be about .090" or so in width.
-Jeb
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From: The Top of Utah
Originally Posted by VictorRussell'92
What is the proper way to check valve spring height?
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From: Charleston SC
Are they making noise with the valve covers off ? If not check to see if there are any wear marks on the VC from a posible clearnce problem. I know you have probably already checked this just thought I would post just in case.
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St. Jude Donor '03
Originally Posted by CFI-EFI
The installed height of the spring has nothing to do with the lash, preload, or any noise that either could cause.
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St. Jude Donor '03
Originally Posted by FD2BLK
Are they making noise with the valve covers off ? If not check to see if there are any wear marks on the VC from a posible clearnce problem. I know you have probably already checked this just thought I would post just in case.
They aren't hitting the covers but I need the obvious answers too!
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St. Jude Donor '03
Originally Posted by HammerDown
How loud are they, Vic? The valvetrain is going to be noisier than the stock LT1 setup.
Not so bad, I listened to Matts LT-4 (has the exact same setup) and its sounds the same but mine is a little louder. I know the sewing machine sound is to be expected but I do get a noticable tic at higher RPMs.
I just ordered a new set of compcam lifters and hardened pushrods. I'm hoping that will set me straight. Prolly shouldn't have used the stock lifters especially with the milage on em but they all looked so pretty.
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From: The Top of Utah
Originally Posted by VictorRussell'92
They aren't hitting the covers but I need the obvious answers too!
Have you tried different amounts of preload? For some reason, that makes no sense to me, some forum members report that increasing the preload closer to a full turn from zero lash, has made their valve train quieter than only a 1/4 or a 1/2 turn.
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St. Jude Donor '03
Originally Posted by CFI-EFI
Are the rocker arms hitting the spring retainers?
Have you tried different amounts of preload? For some reason, that makes no sense to me, some forum members report that increasing the preload closer to a full turn from zero lash, has made their valve train quieter than only a 1/4 or a 1/2 turn.
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Have you tried different amounts of preload? For some reason, that makes no sense to me, some forum members report that increasing the preload closer to a full turn from zero lash, has made their valve train quieter than only a 1/4 or a 1/2 turn.
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My first two attempts at preload was 1/2 a turn past zero lash. Now I'm trying 3/4 turn. Tic is still present. The tic is noticeable and it is at higher rpm. I think I might have issues with pitted lifters or something. I have adjusted these things probably 4 times total using the helms service manual method, a great method Agent 86 gave me, and other forum member tips.
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From: The Top of Utah
It can be a lot less time consuming, for multiple preload settings, and you get instant results, if you set the preload while the engine is running. It's also a lot easier to determine the zero lash point. FWIW.
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Drifting
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From: Huntsville AL
Have you asked Nathan what his sounds like?
Todd said he thought as long as there aren't one or two rockers making all the noise, you were probably ok. We can hear ticking in my valvetrain, and I still have the LT1 stockers. But all 16 sound the same.
Todd said he thought as long as there aren't one or two rockers making all the noise, you were probably ok. We can hear ticking in my valvetrain, and I still have the LT1 stockers. But all 16 sound the same.
Last edited by HammerDown; Jul 1, 2005 at 10:59 AM.
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St. Jude Donor '03
Yeah still on the stock injectors. Don't plan on changing em either. I may one day get the FMS 24lbs ers just so I know they are flowing perfectly.
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St. Jude Donor '03
Originally Posted by HammerDown
Have you asked Nathan what his sounds like?
Todd said he thought as long as there aren't one or two rockers making all the noise, you were probably ok. We can hear ticking in my valvetrain, and I still have the LT1 stockers. But all 16 sound the same.
Todd said he thought as long as there aren't one or two rockers making all the noise, you were probably ok. We can hear ticking in my valvetrain, and I still have the LT1 stockers. But all 16 sound the same.
Pretty sure it is one or two rockers making the tic noise. I have tried the adjust while the motor is running trick but since my tic is only at higher RPM this does not work with all the oil spray!
Drifting
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From: Huntsville AL
Have you used a stethoscope or long screwdriver on the valve covers at each rocker location to see if there are any that are louder than the others? That's what we did on mine, and they all sounded pretty much the same. That will at least help you isolate the problem.