Rocker questions
Rocker questions So just changed valve springs. When reinstalling the rockers can I just bolt down to 22ft lbs and be done. Or do i have to adjust based on intake and exhaust valve
Also, on the picture showing the bottom of rocker you can see where the rocker has been rubbing and has caused some marks dug into the metal...what is the reason for this and how do I fix it?
First time doing valve and rocker work so just want to make sure this baby is 100% when it gets it back together.
Also, on the picture showing the bottom of rocker you can see where the rocker has been rubbing and has caused some marks dug into the metal...what is the reason for this and how do I fix it?
First time doing valve and rocker work so just want to make sure this baby is 100% when it gets it back together.
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That doesn't look like it's made to go in a stock valve train. (not a stock LSx that is)
The gouges look like where they were smashed against the stock guide stands.
Looks like it's time to do away with all that and put something on that fits. Even just, stock rockers, maybe with a bushing trunnion upgrade.
The gouges look like where they were smashed against the stock guide stands.
Looks like it's time to do away with all that and put something on that fits. Even just, stock rockers, maybe with a bushing trunnion upgrade.
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It's a LS1 motor.
All this was done by the previous owner. Has 7.350 crane pushrods and these rockers. Trying to correct all this madness now LOL
I believe it has the individual stud. Here is a picture
All this was done by the previous owner. Has 7.350 crane pushrods and these rockers. Trying to correct all this madness now LOL
I believe it has the individual stud. Here is a picture
Lol, I knew it! You might just have too short of pushrods which are allowing the rockers to rub against the radius at the bottom of the stud. If I were you, I would try different longer pushrods. It might help the rocker geometry too.
So just changed valve springs. When reinstalling the rockers can I just bolt down to 22ft lbs and be done. Or do i have to adjust based on intake and exhaust valve
Also, on the picture showing the bottom of rocker you can see where the rocker has been rubbing and has caused some marks dug into the metal...what is the reason for this and how do I fix it?
First time doing valve and rocker work so just want to make sure this baby is 100% when it gets it back together.
Also, on the picture showing the bottom of rocker you can see where the rocker has been rubbing and has caused some marks dug into the metal...what is the reason for this and how do I fix it?
First time doing valve and rocker work so just want to make sure this baby is 100% when it gets it back together.
Those are Crane 1.8 Quick Lift rockers. To answer your original question, no you can't simply bolt in and tighten like stock. They are stud mounted rockers and each turn of the poly lock will increase your lifter preload. Not sure what lifters you have, but note also the studs are 8mm where they go into the head but the thread facing up is an SAE thread. You should have pushrod guide plates mounted on the heads and hardened pushrods for use with the guide plates. They shouldn't contact anything on the bottom is correctly installed.
What length are your pushrods? They may be too short lowering the rocker and causing contact.
Those are Crane 1.8 Quick Lift rockers. To answer your original question, no you can't simply bolt in and tighten like stock. They are stud mounted rockers and each turn of the poly lock will increase your lifter preload. Not sure what lifters you have, but note also the studs are 8mm where they go into the head but the thread facing up is an SAE thread. You should have pushrod guide plates mounted on the heads and hardened pushrods for use with the guide plates. They shouldn't contact anything on the bottom is correctly installed.
What length are your pushrods? They may be too short lowering the rocker and causing contact.
What length are your pushrods? They may be too short lowering the rocker and causing contact.
Originally, the Crane rockers were supplied with 7.250" pushrods. The AFR heads required a different length, I think those were the 7.350". The pushrod cup is greatly changed from stock, hence a different pushrod length is required. As for the contact, you don't recall how many turns came off the rockers when you removed them do you? The pushrod will set geometry and preload, so be careful of any changes. Think I might shine a light on the valve tips and see if you can verify where the contact patch is located (i.e., wipe pattern).
Originally, the Crane rockers were supplied with 7.250" pushrods. The AFR heads required a different length, I think those were the 7.350". The pushrod cup is greatly changed from stock, hence a different pushrod length is required. As for the contact, you don't recall how many turns came off the rockers when you removed them do you? The pushrod will set geometry and preload, so be careful of any changes. Think I might shine a light on the valve tips and see if you can verify where the contact patch is located (i.e., wipe pattern).
Anyways, would a shorter or a longer pushrod be needed in a situation like this? The heads on the car are oem
I am doing this from memory, you might want to contact Vinci and see if they will answer your questions.
I would install one rocker that you can easily view and bring it to zero lash with lifter on base circle. Then tighten the nut 1-1/2 turns and check clearance to the hex head on the rocker stud. The pushrod length and preload (number of turns) will determine the clearance.
The other thing I would do is then install a check spring and bring to zero lash again and then put sharpie on the valve stem and check the wipe pattern by moving the rocker by hand through the computed lift.
I would install one rocker that you can easily view and bring it to zero lash with lifter on base circle. Then tighten the nut 1-1/2 turns and check clearance to the hex head on the rocker stud. The pushrod length and preload (number of turns) will determine the clearance.
The other thing I would do is then install a check spring and bring to zero lash again and then put sharpie on the valve stem and check the wipe pattern by moving the rocker by hand through the computed lift.
I am doing this from memory, you might want to contact Vinci and see if they will answer your questions.
I would install one rocker that you can easily view and bring it to zero lash with lifter on base circle. Then tighten the nut 1-1/2 turns and check clearance to the hex head on the rocker stud. The pushrod length and preload (number of turns) will determine the clearance.
The other thing I would do is then install a check spring and bring to zero lash again and then put sharpie on the valve stem and check the wipe pattern by moving the rocker by hand through the computed lift.
I would install one rocker that you can easily view and bring it to zero lash with lifter on base circle. Then tighten the nut 1-1/2 turns and check clearance to the hex head on the rocker stud. The pushrod length and preload (number of turns) will determine the clearance.
The other thing I would do is then install a check spring and bring to zero lash again and then put sharpie on the valve stem and check the wipe pattern by moving the rocker by hand through the computed lift.
