Possible 1st Yella Terra rocker failure
11-09-2012, 07:57 AM
#101
I ended up ordering and installing the Harland sharp rockers. They are made specifically for the trick flow heads.
I did have to grind down the numbs inside the valve covers as they hit. Now I'm wondering if the YT's would hit when I would hit the rev limiter? Think that's possible? Do the rockers go up higher with vavle float?
I did have to grind down the numbs inside the valve covers as they hit. Now I'm wondering if the YT's would hit when I would hit the rev limiter? Think that's possible? Do the rockers go up higher with vavle float?
05-15-2013, 10:25 AM
#104
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Driving my 2007 LS2 vette 23,000 miles quite gently when all of a sudden start hearing loud banging noises from engine so dip the clutch and pull over get a tow back home.
Now engine has a few mods Lingenfelter: Cold Air Intake, GT11 cam 215/231 .631/.644 118.0 C5R timing chain. LPE Large valve ported heads. 2.055" / 1.57". Yella roller rockers. Manta pushrods. Ported throttlebody and Fast 92mm intake. TB Spacer. 47 lbs. injectors. Kooks 1 3/4 headers with High Flow converters. Lingenfelter: Cold Air Intake, GT11 cam 215/231 .631/.644 118.0 C5R timing chain. LPE Large valve ported heads. 2.055" / 1.57". Yella roller rockers. Manta pushrods. Ported throttlebody and Fast 92mm intake. TB Spacer. 47 lbs injectors. Kooks 1 3/4 headers with High Flow converters.
I was just about to change the dual valve springs which I had just received along with spring compressor and airline fitting to keep valves up and fault this may have been problem as existing had close to 12,000 miles on them.
So removed valve covers and find one rocker snapped in two push rod looks ok on first inspection and can’t see any other stress marks on the other rockers. After a bit of a search round the internet looks like there have been a few failures of these rockers and he manufactures have recently upgraded them.
So questions
• Is there likley to be any damage to cylinder heads vales from a snapped rocker?
• Best replacement for my car or use these updated Yella rockers.
• I have new double springs and compressor tool to stop valve dropping is it much of a job to change the rockers at the same time, and DIY wright ups.
http://i1082.photobucket.com/albums/...ps37c39164.jpg
Now engine has a few mods Lingenfelter: Cold Air Intake, GT11 cam 215/231 .631/.644 118.0 C5R timing chain. LPE Large valve ported heads. 2.055" / 1.57". Yella roller rockers. Manta pushrods. Ported throttlebody and Fast 92mm intake. TB Spacer. 47 lbs. injectors. Kooks 1 3/4 headers with High Flow converters. Lingenfelter: Cold Air Intake, GT11 cam 215/231 .631/.644 118.0 C5R timing chain. LPE Large valve ported heads. 2.055" / 1.57". Yella roller rockers. Manta pushrods. Ported throttlebody and Fast 92mm intake. TB Spacer. 47 lbs injectors. Kooks 1 3/4 headers with High Flow converters.
I was just about to change the dual valve springs which I had just received along with spring compressor and airline fitting to keep valves up and fault this may have been problem as existing had close to 12,000 miles on them.
So removed valve covers and find one rocker snapped in two push rod looks ok on first inspection and can’t see any other stress marks on the other rockers. After a bit of a search round the internet looks like there have been a few failures of these rockers and he manufactures have recently upgraded them.
So questions
• Is there likley to be any damage to cylinder heads vales from a snapped rocker?
• Best replacement for my car or use these updated Yella rockers.
• I have new double springs and compressor tool to stop valve dropping is it much of a job to change the rockers at the same time, and DIY wright ups.
http://i1082.photobucket.com/albums/...ps37c39164.jpg
05-15-2013, 09:18 PM
#109
I've broken 2 from 2 different sets. One breakage I had to pull the head to get all the pieces out. Confidence is low with them as far as I'm concerned. I have a set ot CHE bushed rockers on the bench now waiting for time to put them in along with a set of 11/32 Mantic PR's. My valvetrain has/is setup well with 11/32 PRs and PAC 1521 springs. The CHE rockers are stock rockers bushed with unobtainium and Richard at WCCH (proheads.com) has yet to see a failure. They are good for .650 lift so I'm good at .643.
05-16-2013, 09:49 AM
#110
Launching!
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I've broken 2 from 2 different sets. One breakage I had to pull the head to get all the pieces out. Confidence is low with them as far as I'm concerned. I have a set ot CHE bushed rockers on the bench now waiting for time to put them in along with a set of 11/32 Mantic PR's. My valvetrain has/is setup well with 11/32 PRs and PAC 1521 springs. The CHE rockers are stock rockers bushed with unobtainium and Richard at WCCH (proheads.com) has yet to see a failure. They are good for .650 lift so I'm good at .643.
For the particular TFS heads I am running I have to use a full roller rocker. If I change heads, I will most likely have to change rockers (thinking about LS3 style head)
