Quick HELP needed!! Anyone using Comp Cams Pro Magnum 1.85 (or other) Rockers inside!
05-07-2005, 02:56 PM
#1
On The Tree
Thread Starter
Join Date: Nov 2004
Location: Macomb Township, MI
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
Quick HELP needed!! Anyone using Comp Cams Pro Magnum 1.85 (or other) Rockers inside! Ok I for one HATE making posts like this, but unfortunately I'm on a deadline and I have no choice 
I'm RIGHT in the middle of putting Comp Cams 1.85:1 Pro Magnum Roller Rockers on an LS1. This kit did NOT come with instructions and I'm not used to not using a rocker guideplate ect. So I need some relatively simple info 
1. Is the assembly process:
1. Pushrod guideplate
2. Rocker Stud
3. Rocker
4. Rocker Nut
(on paper this looks to be perfect, just curious)
2. Next, WTF do I set lash to on these things 0? 0+ 1/4 turn? What, like I said no instructions make this pretty damn hard so any info would be greatly appreciated guys! Thanks!
I'm RIGHT in the middle of putting Comp Cams 1.85:1 Pro Magnum Roller Rockers on an LS1. This kit did NOT come with instructions and I'm not used to not using a rocker guideplate ect. So I need some relatively simple info 1. Is the assembly process:
1. Pushrod guideplate
2. Rocker Stud
3. Rocker
4. Rocker Nut
(on paper this looks to be perfect, just curious)
2. Next, WTF do I set lash to on these things 0? 0+ 1/4 turn? What, like I said no instructions make this pretty damn hard so any info would be greatly appreciated guys! Thanks!
05-08-2005, 05:58 PM
#3
Staging Lane
Join Date: Oct 2004
Location: Grand Blanc, Michigan
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
I have the 1.75:1 Pro-Mag rockers on my LS1. With a hydrolic cam, I don't think it is refered to as "lash". I think it is refered to as "preload". This is the procedure I followed when I set mine and they are running fine:
I had a hand held push button that hooked up to my starter to turn the motor over when you push the button. Mine is from Snap-On, but I think you may be able to get one from you local autoparts store.
1. Disconnect your coil packs so the car wont start.
2. Snug down all rocker nuts as tight as you can get them with your fingers (be sure the jam nut is backed off enough so it won't make contact with the top of the stud).
3. Turn the motor over until there is oil coming out of the holes on the pushrod end of the rocker (now you know your lifters are pumped up).
4. As you turn the motor over to pump up the lifters, stop every now and then to take a few seconds to double check the nuts on the rockers to make sure they are all snug.
5. Once you have oil coming out of the holes in the ends of all the rockers you can start with any cylinder.
6. Now bump the motor and watch the intake valve. When it goes down and comes all the way back up and stops, set the EXHAUST ROCKER.
You set the preload buy making sure the nut is finger tight, then go 3/4 of a turn tighter. I put a dab of red loctite on all my lock nuts and tightened them down after setting the preload on that valve.
7. While you are on the same cylinder, bump the motor until you see the exhaust valve go down and come back up and stop. Now set the INTAKE ROCKER. Set it the same way you set the exhaust rocker.
Follow this procedure for all 8 cylinders and you should be fine. I marked the tops of the rocker nuts with a paint marker after I finished so I knew which ones had been done. Also make sure that your rocker studs are torqued down to 25 ft.lbs. I also put a dab of red loctite on them before torquing.
I had a hand held push button that hooked up to my starter to turn the motor over when you push the button. Mine is from Snap-On, but I think you may be able to get one from you local autoparts store.
1. Disconnect your coil packs so the car wont start.
2. Snug down all rocker nuts as tight as you can get them with your fingers (be sure the jam nut is backed off enough so it won't make contact with the top of the stud).
3. Turn the motor over until there is oil coming out of the holes on the pushrod end of the rocker (now you know your lifters are pumped up).
4. As you turn the motor over to pump up the lifters, stop every now and then to take a few seconds to double check the nuts on the rockers to make sure they are all snug.
5. Once you have oil coming out of the holes in the ends of all the rockers you can start with any cylinder.
6. Now bump the motor and watch the intake valve. When it goes down and comes all the way back up and stops, set the EXHAUST ROCKER.
You set the preload buy making sure the nut is finger tight, then go 3/4 of a turn tighter. I put a dab of red loctite on all my lock nuts and tightened them down after setting the preload on that valve.
7. While you are on the same cylinder, bump the motor until you see the exhaust valve go down and come back up and stop. Now set the INTAKE ROCKER. Set it the same way you set the exhaust rocker.
Follow this procedure for all 8 cylinders and you should be fine. I marked the tops of the rocker nuts with a paint marker after I finished so I knew which ones had been done. Also make sure that your rocker studs are torqued down to 25 ft.lbs. I also put a dab of red loctite on them before torquing.
05-09-2005, 05:39 AM
#4
11 Second Club
Join Date: Nov 2001
Location: NE PA
Posts: 1,320
Likes: 0
Received 0 Likes
on
0 Posts
Here are some pretty good instructions from the Crane web site. Remember that you can "bump" the motor with the starter to accomplish this as long as you have someone there to assist you.
Adjusting Hydraulic Lifters for Proper Preload
In order to adjust the preload the lifter must be properly located on the base circle or “Heel” of the lobe. At this position the valve is closed and there is no lift taking place. You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.
1. Remove the valve covers, and pick a cylinder you are going to set the preload on.
2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder’s intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)
3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)
4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the pushrod, you are at “Zero Lash”. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.
5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.
6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.
Adjusting Hydraulic Lifters for Proper Preload
In order to adjust the preload the lifter must be properly located on the base circle or “Heel” of the lobe. At this position the valve is closed and there is no lift taking place. You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.
1. Remove the valve covers, and pick a cylinder you are going to set the preload on.
2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder’s intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)
3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)
4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the pushrod, you are at “Zero Lash”. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.
5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.
6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.
