Valve Lash Dispute Needs Quick Resolution

[ZR1TR]

My friend told me that I should have #1 on TDC to adjust the valves. Maybe adjust is the wrong word, because there is no real adjustment, but should the motor be on #1 TDC when I torque the factory rocker shaft to 25lbs?

I don't think it matters, since it is a torque spec and not a lash adjustment. It shouldn't matter where the valve train is, when I torque it down.

I am about to go home at lunch and torque it down, so if some could respond ASAP it would be appreciated.

Jonathan

 

[ZR1TR]

Anyone?

This can't be a mystery. I have seen posts about aftermarket rockers but nothing for stock.

HELPPPPPPPPPPPPPPPPPPPP

 

[gofstbuick]

Valve stem height is all that matters. You just need to torque the rocker shaft down. There is no adjustment. You could check valve lash on #1 if the cam is in the #1 position, but you cannot change the results at the rocker arm without making valve train changes. Please explain to your friend that this isn't a cheby engine, and valve lash changes require valve train modifications.

 

[ZR1TR]

Thanks for the info. That's what I thought.

And actually my friend isn't one of the usual Chevy mongers. He said he didn't realize it was a shaft system. I swore I told him though. He actually is a big Poncho guy, so he knows what it is like to have a bunch of ignorant chevy guys tell him nice Chevelle or Camaro (he has a Goat and a T/A). Not to mention all the "is that a small block or big block 400" questions.

 

[1ARUNEM]

You can't adjust all valves on a chevy at TDC either.. Have to adjust when on base of cam lobe for each valve.

 

[1badTTA]

Even on his Poncho engines, there is no adjustment even though they are stud mounted. Just torque them down and go unless you install the big block cheby studs.

<====Owned a few Poncho engines in my days.

Still laughing about the small or big block Ponchos

 

[ZR1TR]

Yeah, I know with BBC studs you need to run polylocks and use a feeler gauge and adjust the valves at TDC for each cylinder.

I owned Pontiacs myself and I always had to roll the motor and adjust each valve on the compression stroke, with the stamped steel rockers.

At least on a Pontiac you have minimal adjustment at each rocker arm.

 

[gofstbuick]

Originally posted by 1ARUNEM
You can't adjust all valves on a chevy at TDC either.. Have to adjust when on base of cam lobe for each valve.

Actually as stated, this is the most correct method. TDC get you in the ball park, but adjusting the intake once the exhaust valve begins to open and the exhaust once the intake is 2/3 open will get you to close or at base circle on the cam for you to make a lash adjustment.