I'm finding lots of conflicting info on this topic. And not just on the internet either. My Chilton's manual gives a valve adjustment procedure that is very SBC-like...make sure pushrod is on base circle of cam, one cylinder at a time, set valves to 1 turn past zero lash, tighten the lock nut, etc...

BUT...on a Pontiac? This just seems flat-out wrong. My 1968 400 doesn't even HAVE locking nuts on the valvetrain...so I'm pretty sure they won't stay in place if I follow that routine and they'll back off. I'm much less familiar with these Pontiacs, but I've always been of the understanding that they are non-adjustable. You tighten the rocker nut all the way, torque them to 20 ft lbs, and call it a day...

What is correct? Back in 1999-ish, I put an engine into storage and relaxed all the valve springs as part of storage procedure. It is now time to bring-er back to life. Do I just crank them down to 20 ft lbs? If yes, I don't even need to rotate the engine to do this, do I? Seems it wouldn't even matter what position the valves are in if I'm just putting them down all the way and giving them a torque spec.

Or does someone sell a set of poly-lock nuts that allow the SBC routine? If yes, is there any benefit to buying a set and running the locked nuts backed off a bit to allow less tension and friction in the valvetrain?

Thanks for clarification and tips!

If it is stock Pontiac valve train just set to 20 lbs.

Yup, just tighten them down . that will set the preload on the lifters. its not like a chevy where you can adjust . its precalculated by the engineers to be set correctly when torqued to 20 lbs.

Mine has big block chevy 7/16 studs/ rockers so mine adjust like a chevy.

That's pretty much what I thought...it just seems wierd that they need to go several full turns past zero lash before they bottom out...

So no need for me to even rotate the engine for this process I guess. Valves can be open or closed for this procedure?

Thanks much for confirming my thought process!

Yup , just torque them down, 20 lbs done.

I have Poly-loks on my valves, is this wrong, the engine builder installed them?

Is this wrong? No. You'll see above that PCI_raid has them on his. But are poly locks "correct" for a 67 Pontiac in terms of originality? Also No.

Take the following with grain of salt as I'm no Pontiac pro. Generically speaking:

Poly-locks are fairly commonly added as part of a performance upgrade, on a Pontiac it seems they usually are put in in conjunction with changing out the factory rocker studs, and they are pretty much mandatory with an upgrade to full roller rockers. You don't often see them on factory stamped rocker arms, but they are absolutely necessary if you want adjustable valve lash, which is often needed if you have a very aggressive camshaft profile.

Actually I have a mild cam, the whole valve train was upgraded from stock.
It all matches the Cam spec's, I was wondering if I needed them because of the upgrade.
I just realize the only thing on my engine rebuild that isn't like stock is the cam, the rockers have the same as stock ratio, Valve stem lenth is at 4.937, stock was 4.932 and my push rods appear to be stock lenth.