Posted By: CR8CRSHR
Define Valve Lash Please.... - 08/22/12 12:17 AM
Define Valve Lashing...
OK....I am having the most difficult time getting my roller rockers to quiet down on a newly re-built 383. Just some quick particulars...
1965 383 block with stock crank, rods, 516 heads,etc. Pistons are HP slugs and the cam is a mild 2328 from Hughes. I am also using their MOPAR specific roller rockers and push rods with Comp Cams valve springs rated for a max lift of .525. The cam has a max lift @ 1.5 rocker ratio of .518. New valve guides, hardened seats, shims to get the springs equal, keepers and guides. Now before I get hammered for using them, I am running the CAT roller rockers. They are the same ones as on my last 383 build which is exactly the same as this one. I have had no issues with them what so ever.
Any way...I am still getting noise out of the left and right valve covers after lashing the rockers on 3 previous occasions. This time I backed them out fully and then using Don Taylor's Big Block Book which is my build bible, I re-lashed them again. Motor fired right up but I am still getting chatter. Now here is the question????
When lashing the valves/rockers what is the acceptable and most common way of determining the "resistance" when setting the lash. Is it when the rocker adjuster ball is seated in the push rod cup and no longer will move up or down but still turn or rotate while in position?????? And then adding say a 1/2 turn additional to fully set them or...
Using the same above technique, obtain resistance up and down along with the no rotation of the push rod and then a 1/2 turn to set them?
The key word here is "Resistance". I have had them too tight and no engine fire up so that is not the issue now. Just cannot get them to quiet down and it is really getting annoying trying to get them to quit. Other than that, the motor is running and no leaks...unless you leave the valve covers loose on the head and you wind up with an oil spill underneath and smoke in the shop from the oil burning on the exhaust...
OK....I am having the most difficult time getting my roller rockers to quiet down on a newly re-built 383. Just some quick particulars...
1965 383 block with stock crank, rods, 516 heads,etc. Pistons are HP slugs and the cam is a mild 2328 from Hughes. I am also using their MOPAR specific roller rockers and push rods with Comp Cams valve springs rated for a max lift of .525. The cam has a max lift @ 1.5 rocker ratio of .518. New valve guides, hardened seats, shims to get the springs equal, keepers and guides. Now before I get hammered for using them, I am running the CAT roller rockers. They are the same ones as on my last 383 build which is exactly the same as this one. I have had no issues with them what so ever.
Any way...I am still getting noise out of the left and right valve covers after lashing the rockers on 3 previous occasions. This time I backed them out fully and then using Don Taylor's Big Block Book which is my build bible, I re-lashed them again. Motor fired right up but I am still getting chatter. Now here is the question????
When lashing the valves/rockers what is the acceptable and most common way of determining the "resistance" when setting the lash. Is it when the rocker adjuster ball is seated in the push rod cup and no longer will move up or down but still turn or rotate while in position?????? And then adding say a 1/2 turn additional to fully set them or...
Using the same above technique, obtain resistance up and down along with the no rotation of the push rod and then a 1/2 turn to set them?
The key word here is "Resistance". I have had them too tight and no engine fire up so that is not the issue now. Just cannot get them to quiet down and it is really getting annoying trying to get them to quit. Other than that, the motor is running and no leaks...unless you leave the valve covers loose on the head and you wind up with an oil spill underneath and smoke in the shop from the oil burning on the exhaust...