Rocker arm install help!
Thread Starter
Pro
Joined: Jan 2014
Posts: 631
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From: NEWPORT NEWS VIRGINIA
Rocker arm install help!
Hey guys I am going to swap out my trunnions on my stock rockers arms for added security( LS2 ). This will be the first time I have ever taken the rockers off. I feel I am mechanically inclined to the job but I am not sure how to reinstall install them. Meaning will I have to check preload or etc. Can someone give me a break down of the easiest and best way to make sure it right.
I youtubed it but it all seems to talk about adjustable rocker arms or aftermarket.
I youtubed it but it all seems to talk about adjustable rocker arms or aftermarket.
Melting Slicks
Joined: Mar 2011
Posts: 2,708
Likes: 83
From: Arkansas
The LS series rockers are zero lash. Here's the proper way of torqueing the rocker arms.
The Number 1 piston is at the compression stroke when the Number 6 cylinder inlet and exhaust valves are rocking, that is when the exhaust valve is at the end of its upward travel while the intake valve starts its downward movement.
Rotate the crankshaft until number one piston is at top dead center of compression stroke.
With the engine in the number one firing position, tighten the following valve rocker arm retaining bolts. Tighten exhaust valve rocker arm retaining bolts 1, 2, 7, and 8 to 30 Nm (22 lb ft). Tighten intake valve rocker arm retaining bolts 1, 3, 4, and 5 to 30 Nm (22 lb ft).
Rotate the crankshaft 360 degrees.
Tighten the following valve rocker arm retaining bolts. Tighten exhaust valve rocker arm retaining bolts 3, 4, 5, and 6 to 30 Nm (22 lb ft). Tighten intake valve rocker arm retaining bolts 2, 6, 7, and 8 to 30 Nm (22 lb ft).
The Number 1 piston is at the compression stroke when the Number 6 cylinder inlet and exhaust valves are rocking, that is when the exhaust valve is at the end of its upward travel while the intake valve starts its downward movement.
Rotate the crankshaft until number one piston is at top dead center of compression stroke.
With the engine in the number one firing position, tighten the following valve rocker arm retaining bolts. Tighten exhaust valve rocker arm retaining bolts 1, 2, 7, and 8 to 30 Nm (22 lb ft). Tighten intake valve rocker arm retaining bolts 1, 3, 4, and 5 to 30 Nm (22 lb ft).
Rotate the crankshaft 360 degrees.
Tighten the following valve rocker arm retaining bolts. Tighten exhaust valve rocker arm retaining bolts 3, 4, 5, and 6 to 30 Nm (22 lb ft). Tighten intake valve rocker arm retaining bolts 2, 6, 7, and 8 to 30 Nm (22 lb ft).
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,629
Note, this only works when you are replacing with same/same.
In the case of changing out LS2 lifters with LS7 lifters, the difference from the end of the roller to the seating point of the push rod seat in the lifter is .050" different , which requires different push rods as well (looking for a .080" pre-load target with the retainer bolt at 22ftlbs) .
In the case of changing out LS2 lifters with LS7 lifters, the difference from the end of the roller to the seating point of the push rod seat in the lifter is .050" different , which requires different push rods as well (looking for a .080" pre-load target with the retainer bolt at 22ftlbs) .
Thread Starter
Pro
Joined: Jan 2014
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From: NEWPORT NEWS VIRGINIA
I had everything working fine before... the shop set everything up when doing the h/c/I install. During this time I forgot to ask them to change out the trunnions so I am using the same rockers. I am just changing the trunnions out and reinstalling the rockers.
Last edited by shawnaj7731; Oct 10, 2014 at 09:34 PM.
Melting Slicks
Joined: Mar 2011
Posts: 2,708
Likes: 83
From: Arkansas
STOP!
If everything is fine then leave it be. The shop probably didn't swap the trunions because it's not necessary.
If you Google search the trunion upgrade you will find information that may surprise you. There has been more reported cases of the name brand (COMP CAMS) failing than there have been the oem units.
..............but it's your money anyway. Monitor your oil closely for metal shavings as that is generally the first sign that something (not necessarily the trunions) is failing. You can get oil samples tested at Blackstone Labs for $25.00 a sample. You would be surprised at the information your oil is telling you. No shavings = no problem.
Let me know if you need assistance.
If everything is fine then leave it be. The shop probably didn't swap the trunions because it's not necessary.
If you Google search the trunion upgrade you will find information that may surprise you. There has been more reported cases of the name brand (COMP CAMS) failing than there have been the oem units.
..............but it's your money anyway. Monitor your oil closely for metal shavings as that is generally the first sign that something (not necessarily the trunions) is failing. You can get oil samples tested at Blackstone Labs for $25.00 a sample. You would be surprised at the information your oil is telling you. No shavings = no problem.
Let me know if you need assistance.
Last edited by Speedforhire; Oct 11, 2014 at 09:14 AM.
Thread Starter
Pro
Joined: Jan 2014
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From: NEWPORT NEWS VIRGINIA
that is funny you say that, because I did call him back and ask after it was all said and done and he said it was not a must do. Although My buddy had an issue with his c5 with needle bearings coming out so I thought it was a cheap investment. I was going to go with Brian tooley trunnion kit but I am not sure now. I also got the idea from this forum to do it and 2 performance shops says its must do. so, I am so confused Should I just change the rockers out to something completely aftermarket then? I just don't want to have a mishap like my buddy.
Thread Starter
Pro
Joined: Jan 2014
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From: NEWPORT NEWS VIRGINIA
maybe this is a sign not to mess with them just posted. https://www.corvetteforum.com/forums...n-upgrade.html i think if i am going to change out the rockers i will just go with a complete aftermarket rocker or maybe just leave it . i have been to the track once on the oem and its been about 3k miles on my upgrades and holding so i guess i will just wait.
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Burning Brakes
Joined: Jul 2013
Posts: 823
Likes: 7
From: Rosewood Heights IL
I went with the BTR Trunion upgrade. Brian assured me that he uses better quality bearings than Comp. Cheaper too.
It is a very worthwhile upgrade to prevent stock needle bearings from ruining the engine.
It is a very worthwhile upgrade to prevent stock needle bearings from ruining the engine.
Melting Slicks
Joined: Mar 2011
Posts: 2,708
Likes: 83
From: Arkansas
There's probably more reported cases of the upgrade units failing than there are the oem units.
BTW! Heavy pressure valvetrain components will need replacing every 5-10K miles on average (depending on setup).
BTW! Heavy pressure valvetrain components will need replacing every 5-10K miles on average (depending on setup).
Last edited by Speedforhire; Oct 13, 2014 at 09:08 AM.
Burning Brakes
Joined: Jul 2013
Posts: 823
Likes: 7
From: Rosewood Heights IL
Oh man. "Probably", that's some solid data to back up that claim.
Does "probably" account for install error?
One look at the aftermarket bearing designs when compared to stock shows that they are light years ahead of the factory pieces. Snap rings and actual bearing races compared to a stamped press-fit end cap.
Does "probably" account for install error?
One look at the aftermarket bearing designs when compared to stock shows that they are light years ahead of the factory pieces. Snap rings and actual bearing races compared to a stamped press-fit end cap.
Melting Slicks
Joined: Mar 2011
Posts: 2,708
Likes: 83
From: Arkansas
Typical blog criticism! You're more than welcome to crunch your own data dev1360. Just type it in your favorite search engine and you'll see a plethora of blogs about this issue.
OP has over 3K miles on the oem units without issues. It goes back to the old saying: If it ain't broke don't fix it!
BTW! Heavy pressure valvetrain components will need replacing every 5-10K miles on average (depending on setup) because of wear.
OP has over 3K miles on the oem units without issues. It goes back to the old saying: If it ain't broke don't fix it!
BTW! Heavy pressure valvetrain components will need replacing every 5-10K miles on average (depending on setup) because of wear.
Pro
Joined: Apr 2013
Posts: 749
Likes: 56
From: Northern VA
I did the CC trunion upgrade last month while I was doing aftermarket valve covers. I've put over 3k miles on my car since then and some of those miles were "spirited" (we'll just leave it at that). No issues at all and it's actually running quieter than when I was using stock rocker arms. Just my experience with the product. Like you I was also concerned about needle bearings coming out of the stock rocker arms. In regards to a complete aftermarket rocker arm setup...I have a friend that had Harland Sharp rocker arms on his GTO and one actually broke while he was on a road trip (the rocker arm itself). I look at some of the stock parts like I did with the C6 Z06 brake rotors only being drilled for the driver's side...a GM cost saving measure. Where else did they employ "cost saving" measures??? Good luck which ever way you go.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
Over at LS1Tech or google, most CC trunion upgrade failed, attributed to problem with installer, especially the early start. Most just macho out and not using or not understanding what is good shop practice. Procedures were basically crude to say the least. A "hammer mechanic" job - literally using a hammer and punch in a dirty environment - emphasizing how fast they can do the job.
Using CHE eliminated that trunion install operator problem, require user send in rockers and they do the job for you, only!
My CC trunions been in the car for awhile and they are "quietly" doing their job.
Using CHE eliminated that trunion install operator problem, require user send in rockers and they do the job for you, only!
My CC trunions been in the car for awhile and they are "quietly" doing their job.
Pro
Joined: Apr 2013
Posts: 749
Likes: 56
From: Northern VA
Over at LS1Tech or google, most CC trunion upgrade failed, attributed to problem with installer, especially the early start. Most just macho out and not using or not understanding what is good shop practice. Procedures were basically crude to say the least. A "hammer mechanic" job - literally using a hammer and punch in a dirty environment - emphasizing how fast they can do the job.
Using CHE eliminated that trunion install operator problem, require user send in rockers and they do the job for you, only!
My CC trunions been in the car for awhile and they are "quietly" doing their job.
Using CHE eliminated that trunion install operator problem, require user send in rockers and they do the job for you, only!
My CC trunions been in the car for awhile and they are "quietly" doing their job.
My CC trunions were professionally upgraded. I was not about to attempt to do it myself with a table vice and a hammer. I am glad I had the technical ability to install the upgraded rocker arms myself and they are performing very nicely. I'm sending my stock rocker arms (my "core" exchange) to the vendor that sold me the upgraded rocker arms as an already installed kit.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
My CC trunions were professionally upgraded. I was not about to attempt to do it myself with a table vice and a hammer. I am glad I had the technical ability to install the upgraded rocker arms myself and they are performing very nicely. I'm sending my stock rocker arms (my "core" exchange) to the vendor that sold me the upgraded rocker arms as an already installed kit.I did mine after I machined precise fit drift push pin and using my mill as a press. It does take a little finesse and perpendicular squareness to avoid damaging the new bearing cage and understand new "C" clips can easily overstretched to avoid failure.
Last edited by victorf; Nov 16, 2014 at 01:37 PM.
Racer
Joined: Jun 2013
Posts: 250
Likes: 12
From: Manayunk PA
My advice... I had a GTO with a .614/.614 lift cam and bone stock lifters for 50k miles with no problems. My corvette had an aftermarket cam for 60k miles and now another 10k miles on my fresh motor build with bone stock rockers. Leave them stock... if they ain't broke, don't fix them.