New Guy on the block with LS issues
08-26-2013, 09:00 PM
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New Guy on the block with LS issues Hi everyone im new to this site but not new to LS engine i have 2 now and a third on the way 
however the third one is what has brought me here. i have a 2003 silverado 1500 i pulled the weak 5.3L and put in a LQ4 with 243 heads i have also put in new berings/rings/gaskets/arp bolts and of course a large cam (comp cam 54-455-11)
gross lift .604intake
.610exhaust
tappet lift 264/272
lobe seperation of 112
comp cam called for heavy springs(470lbs open pressure, 125lbs seat pressure, dual coil) also keepers and retainers which i also did, and i finished it of with new comp roller lifters and 1.7 LS scorpion full roller rocker as the OE rockers are common to have the needle bearings walk out under heavy spring pressure, i have run in to some valve cover clearance issuse which i have solved but i am having a few bent push rods.... i re-used the OEM push rods but now im wondering has anyone else run in to issues with OEM pushrods? could it be a result of the high spring pressure or do i have alve clearance issues?(oe head gaskets no block maching at all just ball honed) hope you guys can shead some light on my issues and maybe i can get this solved so i can burn some tires! Thanks for reading and cant wait to chat with all of you!
however the third one is what has brought me here. i have a 2003 silverado 1500 i pulled the weak 5.3L and put in a LQ4 with 243 heads i have also put in new berings/rings/gaskets/arp bolts and of course a large cam (comp cam 54-455-11) gross lift .604intake
.610exhaust
tappet lift 264/272
lobe seperation of 112
comp cam called for heavy springs(470lbs open pressure, 125lbs seat pressure, dual coil) also keepers and retainers which i also did, and i finished it of with new comp roller lifters and 1.7 LS scorpion full roller rocker as the OE rockers are common to have the needle bearings walk out under heavy spring pressure, i have run in to some valve cover clearance issuse which i have solved but i am having a few bent push rods.... i re-used the OEM push rods but now im wondering has anyone else run in to issues with OEM pushrods? could it be a result of the high spring pressure or do i have alve clearance issues?(oe head gaskets no block maching at all just ball honed) hope you guys can shead some light on my issues and maybe i can get this solved so i can burn some tires! Thanks for reading and cant wait to chat with all of you!
08-26-2013, 10:24 PM
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I never checked pushrod length or lifter preload.... Not sure what to look for there? Or really how to check that... Sorry I'm new to engine building. The weird part is that I have 3 bent on the intake valves on bank2 and 4 bent on the exhaust on bank1.
08-27-2013, 11:08 AM
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