Rocker Adjustment
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Rocker Adjustment
I'd like some feedback on converting to roller rockers after having stamped steel and ajusting those for years. Hopefully someone has done this. This is on a bbc 454"
Method used is exh opening - adjust intake --- intake closing - adjust exh
- When you install and adjust a stamped steel rocker and interferance nuts - twisting the pushrod until resistance is felt and turning 1/2 turn past zero lash, the pushrod feels pretty firm and takes a fair amount of pressure to turn it in the lifer. The rocker is also pretty firm on the stud. So far so good.
- Now I am trying to install Summit alum roller rockers, same ratio of 1.7:1.
- When you get to zero lash (which can be done with finger tension - no wrench needed) with the pushrod meeting the same resistance feel as with stamped steel rockers, I turn the trunion 1/2 turn more. This is where I am goosey as the trunion turns super easy and the pushrod just seems to be not as tight as the stamped steel rocker.
Is there something that needs to be done with alum roller rockers as far as turns past zero lash or are they just so much more a precision piece that what I am feeling is normal?
Thanks
Method used is exh opening - adjust intake --- intake closing - adjust exh
- When you install and adjust a stamped steel rocker and interferance nuts - twisting the pushrod until resistance is felt and turning 1/2 turn past zero lash, the pushrod feels pretty firm and takes a fair amount of pressure to turn it in the lifer. The rocker is also pretty firm on the stud. So far so good.
- Now I am trying to install Summit alum roller rockers, same ratio of 1.7:1.
- When you get to zero lash (which can be done with finger tension - no wrench needed) with the pushrod meeting the same resistance feel as with stamped steel rockers, I turn the trunion 1/2 turn more. This is where I am goosey as the trunion turns super easy and the pushrod just seems to be not as tight as the stamped steel rocker.
Is there something that needs to be done with alum roller rockers as far as turns past zero lash or are they just so much more a precision piece that what I am feeling is normal?
Thanks
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
.plus some of your lifters may have bled off when you pulled the original rockers.....
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
remember....EIIEEIIE
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
When I used to build hydraulic motors I would adjust the valves the first time with the intake off so I can get my hand on the pushrod easier. I move it up and down, when no more movement 0 lash.
You said it yourself, stock rocker nuts are interference fit that is why they are harder to turn down. I would go 3/4 of a turn with the polylocks sometimes the cheaper ( not saying you have them ) polylocks will pull up on the nut when you tighten the inside allen keeper screw, therefore you won't have the 3/4 turn anymore, it will be more like 1/2 turn. Just my 2c
You said it yourself, stock rocker nuts are interference fit that is why they are harder to turn down. I would go 3/4 of a turn with the polylocks sometimes the cheaper ( not saying you have them ) polylocks will pull up on the nut when you tighten the inside allen keeper screw, therefore you won't have the 3/4 turn anymore, it will be more like 1/2 turn. Just my 2c
