Hydraulic lifters

[swtman]

I'm putting a new stock 350 camshaft in my stock 305 and I would like to know where to set my backlash at. When I research this I find different answers.Some say 1/4 turn from zero lash...some say 1/2 turn... but Haynes manuals say 1 turn and I believe I saw somewhere GM manuals say 1 turn. Any help would be greatly appreciated!

[Longhorn Man]

I've always done 1/2 past zero personally. They don't need all the preload that GM puts on them. All it does is wear out the cam faster, esp with todays crappy oils.

[piecesparts]

There are write ups on how to do this in many manuals. Cam distributors, like Comp Cams gives the information to rotate the crank assembly to get the lifrer on the back side of the lobe and then take the lash to zero (rotate the push rod with your fingers until it just stops due to resistance) then take the lifter adjustment a 1/2 turn more. (just like Longhorn recommends)

[swtman]

I guess maybe I should just set them at 1/2 turn then???

[prostreetC-10]

Easiest thing to do is lightly roll the pushrod in your fingures until you feel a slight drag (this will be very close to zero lash)....then go 1/2 turn more. 1 turn is too much!

Remember....Haynes manuals are not from the cam makers. They are trying to provide general information.

[prostreetC-10]

Oh yeah and longhorn reminded me of the fact that you need good break-in oil and an additive like EOS or something else to help with zinc on break-in. Get er to 2k-2.5k as quickly as you can and run er for 20 mins. I like to vary rpms every little bit.

[jim zag]

Easy to do!!! When the exhaust valve starts to OPEN set the INTAKE. When the Intake closes set the EXHAUST. I usually go half to three quarters of a turn past zero lash. If you can not find break in additive locally you can use STP it has zinc in it.