Comp pro magnum rocker issues
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I bought a set of the stainless comp pro magnum roller rockers and every time i adjust them like comp says, my car will not start. I believe its the vavles staying open and this is why the car wont start. Do i need shorter pushrods? Someone must have had this issue to.
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Not familiar with Comp's procedure but if they are stud mounted rockers, the pushrod length adjusts both the wipe and the preload so be careful changing length.
You could try Vinci's procedure that they developed for the Crane rockers to see if that works better. Over adjusting will hold the valves open. Also, zero lash is critical in adjustment and I prefer to gently lift the rocker tip to check clearance rather than rotating the pushrod. You could also use a very thin (0.002") feeler gauge between the valve stem and the rocker tip to set zero lash. This will result in minimal error in the final setting.
You could try Vinci's procedure that they developed for the Crane rockers to see if that works better. Over adjusting will hold the valves open. Also, zero lash is critical in adjustment and I prefer to gently lift the rocker tip to check clearance rather than rotating the pushrod. You could also use a very thin (0.002") feeler gauge between the valve stem and the rocker tip to set zero lash. This will result in minimal error in the final setting.
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when i had comp promagnum they adjusted like a smallblock chevy. assumuming you have the correct pushrod length, you adjust preload by the adjusting nut. i was giving 1/2 turn after 0 lash.
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the pushrod length is 7.400 and i did a leak down and the vavles are staying open. I also adjusted them like a old school with 0 lash and a half turn and the motor wont fire.
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I bought a set of the stainless comp pro magnum roller rockers and every time i adjust them like comp says, my car will not start. I believe its the vavles staying open and this is why the car wont start. Do i need shorter pushrods? Someone must have had this issue to.
when the intake valve is 3/4" of the way closed= Adjust your exhaust rocker (0 lash, half turn)
0 lash= no up and down movement in your pushrod.
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The Cranes required a 7.250" pushrod due to the rocker design. If you are using 7.400" because of its closeness to the stock length, then you need to determine the correct length which is a bit more difficult because the length sets both geometry and preload.
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how am i going to check that the motor is in the car and im not going to take off the head to check that. ill have to contact comp to see what size pushrod is recomended