bent pushrods HELP
#1
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bent pushrods HELP
ok so i just dropped in a new motor in my t/a its a built 355 w stock ported heads and a big cam and comp pro mag 1.6 rockers. i just got done breaking in the motor changed the oil and took it out and nailed it through the gears. everything seemed fine at that point but about an hour later i went to move the car and heard a real loud ticking. pulled the valve covers and intake off and on the no. 7 cylinder both pushrods were bent and laying in the valley and one of the rockers was crooked. also i noticed that about 5 or 6 lifters are collapsed as well. this confuses me because i dont believe its an oiling issue because oil pressure was fine, and theres plenty of oil on all the valvetrain, and also i wouldnt suspect a collapsed lifter is the cause of bent pushrods. did a compression test as well and it holds pressure so i dont think the the valve hit the piston. anyone have any ideas on what could have caused this? also would i maybe need to look into some guideplates? any help would be much appreciated thanks. btw i spin the motor at about 6800
#4
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You probably have a geometry problem in the valve train.
Are you running non-self aligning or self-aligniing rockers? If NON-self aligning, are you using guide plates and hardened pushrods?
Did you verify you're using the correct length pushrods?
Did you, or someone else, check all the valve train clearances? pushrod to head; underside of rocker arms to spring retainers, clearance between coils on.
the valve springs, retainers to guide clearance.
Recently, there have been a rash of posts, complete with photos, on failures when guys were running SELF-ALIGNING rocker arms running at higher RPMs.
CompCams recommends NON-SELF ALIGNING rockers in performance applications.
Jake
West Point ROCKS!
Are you running non-self aligning or self-aligniing rockers? If NON-self aligning, are you using guide plates and hardened pushrods?
Did you verify you're using the correct length pushrods?
Did you, or someone else, check all the valve train clearances? pushrod to head; underside of rocker arms to spring retainers, clearance between coils on.
the valve springs, retainers to guide clearance.
Recently, there have been a rash of posts, complete with photos, on failures when guys were running SELF-ALIGNING rocker arms running at higher RPMs.
CompCams recommends NON-SELF ALIGNING rockers in performance applications.
Jake
West Point ROCKS!