Big Boys Toys

454 Cu. Inch big block.
Hydraulic roller tappets.
Roller Rockers.
What would the valve lash be?
Thanks in advance for the reply.
Brian

picklenjim

Zero. Bring down till all up and down movement in the pushrod is gone then give it 3/4 to 1 more turn and lock it down.

tunertech

bring to zero then 1/4 for stock GM lifters. If you are using after market lifters follow the mfg's specs. Most H-Per Lifters are zero plus 1/16th of a trun no more than an 1/8th.

SINGLETGT

or snug all rockers till no up/down play in pushrod. run motor to operating temp. take off valve cover. while running slowly loosen each rocker till you hear tapping. then slowly tighten it till there is no noise, then add 1/4 turn and lock down.

1BIGJIM

iTrader: (1)

Do a search on this topic and you can read until tomorrow morning.

I always go zero 1/2 to 3/4 turn.

35 years ago I was taught to take the valve covers off and adjust that way. To big of a mess. I still have the oil deflecters in one of my tool boxes.

Hard Charger

+1

SINGLETGT

yea I actually have a set of valve covers dedicated for that for when my motor was hydraulic roller. Solid roller now, so now there is lash.

Going the messy route will make the most power tho from what I was told

Griff

X2

txriverrat2001

You do not set a solid lift cam with the engine running - is that what you're thinking?? No way no how. Get the spec's - exhaust is usually more than intake - follow the procedure for placing the cam in the correct position based on the other valve - use a feeler gauge and you're done.

IF I remember correctly - set the intake when the exhaust starts to open - set the exhaust when the intake is about half stroke to being closed...

Don't quote me on it - it's been a while...

picklenjim

UHHHHH.......I don't think anyone was thinking that.