roller rocker help?!?!?!?
Safety Car
Joined: Nov 2005
Posts: 3,961
Likes: 573
From: Lompoc, CA. Santa Barbara County
Just a suggestion. Look long ways down the head. Do all of the rocker arm studs line up. A friend of mine bought some heads where the push in studs were replaced with screw in studs, the holes were not straight, so the studs were not straight. He broke rocker studs too.
Bee Jay
Bee Jay
Pro
Joined: Apr 2006
Posts: 625
Likes: 49
From: Southern California
OK, this is total 
as we all know. They are called guide plates because, well...............they GUIDE the pushrods, which in turn center the rocker arm over the valve tip. That's why guide plates are case hardened, because the pushrods rub on them. The pushrods will transition back and forth between the sides of the guide plate slot edges. Sure there is a transition BETWEEN bumping up against those edges, where they won't be touching, as much as the clearance can allow. But the pushrods most certainly touch the guide plates, a lot. This is how they were designed to work and is perfectly normal. If they never touched, you wouldn't need guide plates in the first place, would you?
It can be very unsettling for newbies to get wrong information from people who appear to know what they are talking about. Take note of who gave this wrong information, and keep that in mind in the future. People who don't know what they are talking about should not be giving information out. Newbies could really be messed up by being told wrong info.
as we all know. They are called guide plates because, well...............they GUIDE the pushrods, which in turn center the rocker arm over the valve tip. That's why guide plates are case hardened, because the pushrods rub on them. The pushrods will transition back and forth between the sides of the guide plate slot edges. Sure there is a transition BETWEEN bumping up against those edges, where they won't be touching, as much as the clearance can allow. But the pushrods most certainly touch the guide plates, a lot. This is how they were designed to work and is perfectly normal. If they never touched, you wouldn't need guide plates in the first place, would you? It can be very unsettling for newbies to get wrong information from people who appear to know what they are talking about. Take note of who gave this wrong information, and keep that in mind in the future. People who don't know what they are talking about should not be giving information out. Newbies could really be messed up by being told wrong info.
Last edited by 540 RAT; Jul 19, 2007 at 07:32 PM.
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
I don't know about the whole guideplate thing, but those are some rather harsh words.
George has been one of the more knowledgable members on the forum and has always provided good advice for engine builds.
George has been one of the more knowledgable members on the forum and has always provided good advice for engine builds.
Pro
Joined: Apr 2006
Posts: 625
Likes: 49
From: Southern California
I'm sure he is a great guy who is well intentioned. Problem is, wrong information is wrong information, no matter who gives it out. I probably wouldn't have called BS on his comment except for the fact that things like this have a occurred from him on a number of occasions before. So, someone needed to warn newbies to beware of whose advice they take. The ramifications of wrong advice/info could be far worse than mere hurt feelings. There are many on this Forum who are quite knowledgeable, others not so much. All I can say is don't believe everything you read on the internet. Of course that dilemma can be nearly impossible for newcomers who don't know any different, to deal with.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I should have said that when you install the guide plates you move them back and forth to get the most centered clearance of the pushrods possible. That way you never have undo binding or friction.I only tighten the rocker studs to where I can still barely move the guide plates. Then I install the pushrods, rocker, rocker locking nuts tight to get firm lash then tighten down the guide plate with the most clearance possible.
Because of the ball end of the pushrods - it keeps the roller rocker very stable. I've watched them run and you don't see the rocker walking back and forth. Even when tearing down my old motors there is no evidence of the pushrod ever scraping the guide plates. I used to wonder why i even bothered to install them
Last edited by gkull; Jul 20, 2007 at 08:37 AM.
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 18
Likes: 0
From: san antonio texas
well before i do anything i always keep asking to make sure 3 or 4 people say the same thing to try to avoid any wrong doing ?!?!?!? ok looks like all studs a in line and while i was taking the rocker all apart i noticed that one push rod is longer by a tenth then all the other ones so i need to get the push rod checker to see exactly what size i need here is some pictures that might help with my problem and the build sheet of the engine!!!
heres the build
heres the build
Le Mans Master
Joined: Apr 2007
Posts: 7,353
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From: Graceland in a Not Correctly Restored Stingray
sidebar: try photobucket to upload your pics into. saves us having to go thru your site's junk to see your shots. Just my $.02. Now back to our regular programming...
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 18
Likes: 0
From: san antonio texas
well i figured this is best keeps people from scrolling down for an hour to get to the nest post and if you need to see it bigger you can click on it if it is the wrong way to do it im sorry
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Le Mans Master
Joined: Apr 2007
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From: Graceland in a Not Correctly Restored Stingray
Appreciate the consideration, but my security software keeps going off whenever I click on the thumbs... Haven't had that problem with other hosts. Maybe it's just me, but thought you should know.
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
The adjustable pushrod length checker is only about $10 at Summit/Jegs, money well spent.... you might need one extra lifter if you use hydraulics, I took one lifter apart, filled it with small shims and reassembled. Now the lifter is solid and won't collapse while rotating the crank
And yes, Imageshack wants you to look at their pop-up advertisements....
And yes, Imageshack wants you to look at their pop-up advertisements....
Instructor
Joined: Mar 2005
Posts: 104
Likes: 0
From: Perkasie PA
I have done this before (ashamed to admit it) with the exact same results. Most likely the springs are not set up correctly and you are getting bind. At full lift you need at least .060 of clearance between the coils in the middle of the spring. Rockers contacting the retainer under the rocker usually marks up the retainer so you will see it by inspecting them. Rocker geometry effects life and RPM potential but would need to be completely F'd to break a stud. All the issues with geometry and push rod guide plates are true and helpful but you break a stud when the spring goes solid.
The only other item that can make it go solid and break a stud is if the valve stem seal is hitting the bottom of the retainer at full lift. Check for .060 here at full lift too.
Cheap and easy geometry check - at half lift the rocker tip should be in the center of the valve. Less than full lift, more on the intake manifold side. Full lift on the exhaust side of the valve tip.
The only other item that can make it go solid and break a stud is if the valve stem seal is hitting the bottom of the retainer at full lift. Check for .060 here at full lift too.
Cheap and easy geometry check - at half lift the rocker tip should be in the center of the valve. Less than full lift, more on the intake manifold side. Full lift on the exhaust side of the valve tip.
Instructor
Joined: Jul 2007
Posts: 228
Likes: 0
From: Price Utah
good idea
Very good information. All points to the importance of checking when we
make changes from original equipment.Aftermarket heads may have been milled, have longer valves etc. Comp cams has very good tech sheets on checking geometry. Please post the resolution to this situation
when discovered.
Thanks and good luck
J Bowles
make changes from original equipment.Aftermarket heads may have been milled, have longer valves etc. Comp cams has very good tech sheets on checking geometry. Please post the resolution to this situation
when discovered.
Thanks and good luck
J Bowles
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 18
Likes: 0
From: san antonio texas
and it is a hydraulic cam
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Coil bind. I don't know how you could rotate a motor over by hand if it has coil bind. But I don't use Hydro lifters. Maybe when they pump up is when you go into bind and break the studs.
Check with the lifter manufacturer, but my AFR heads came with H-roller springs that were for max performance and they were 145 or 150 pound seat and that is about the most that H-lifter can withstand without compressing the plunger
Check with the lifter manufacturer, but my AFR heads came with H-roller springs that were for max performance and they were 145 or 150 pound seat and that is about the most that H-lifter can withstand without compressing the plunger
Pro
Joined: Dec 2006
Posts: 665
Likes: 0
From: wilmington nc
from the looks of your build sheet that"s a pretty healthy hyd. cam your running. Throw in 1.6 rockers even more lift on hyd.
only ran 5 seconds before breaking the second stud, I"d sure be scared of the start me up button on that engine!!!!!!!!
comp has quiet a bit of info on valve trane geometry if you haven"t seen this page allready it may help,
I would think converting one of those hyd. lifters into a solid lifter and see if it will even turn over by hand would be a good place to start.
http://www.compcams.com/Technical/Instructions/
only ran 5 seconds before breaking the second stud, I"d sure be scared of the start me up button on that engine!!!!!!!!
comp has quiet a bit of info on valve trane geometry if you haven"t seen this page allready it may help,
I would think converting one of those hyd. lifters into a solid lifter and see if it will even turn over by hand would be a good place to start.
http://www.compcams.com/Technical/Instructions/
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
i blew up the motor build picture to where i could read the cam specs.
http://www.compcams.com/technical/Ca...67_226-227.pdf
It is the XR294HR on page 19 of the PDF .540/.562 lift. 1.6's will get those 1.5 listed lift numbers higher
http://www.compcams.com/technical/Ca...67_226-227.pdf
It is the XR294HR on page 19 of the PDF .540/.562 lift. 1.6's will get those 1.5 listed lift numbers higher
Safety Car
Joined: Nov 2005
Posts: 3,961
Likes: 573
From: Lompoc, CA. Santa Barbara County
i blew up the motor build picture to where i could read the cam specs.
http://www.compcams.com/technical/Ca...67_226-227.pdf
It is the XR294HR on page 19 of the PDF .540/.562 lift. 1.6's will get those 1.5 listed lift numbers higher
http://www.compcams.com/technical/Ca...67_226-227.pdf
It is the XR294HR on page 19 of the PDF .540/.562 lift. 1.6's will get those 1.5 listed lift numbers higher
I bet he does have coil bind if the valves are not tagging the pistons. 600 lift is huge, isn't it?
Bee Jay
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
Should be just under .600 exhaust lift. What were you promised, as far as engine performance? I only ask cause I think the combo is wrong. Canfield 220 heads, Vic Jr & an Edelbrock carb. It looks like the bigger cam was stuck in there to get back some of the performance lost elsewhere. The build sheet is claiming 587hp @ 6410, I'd have to question that. Someone has stones running hyds up to 6500, unless it has a Hydra-Rev in it. DynoSim has this combo pumping out around 500hp. Not to dis you or anything but the whole shebang looks wrong.
I'll have some time this weekend & could appear with my pushrod checker & maybe help figure this out. PM me with your details.
I'll have some time this weekend & could appear with my pushrod checker & maybe help figure this out. PM me with your details.