69 350 mechanical cam valve lash?

[Steweyfan]

I was wondering if anybody has any info on 69 350... Did they come with a flat tappet cam or just hydraulic? If they did come with a solid lift cam what are the factory specs on the valve lash?
Thanks for any input
Paul

 

[melsg5]

A flat tappet cam can be hydraulic or solid and Pontiac did not use a solid in the 350. Pontiac engines use a bottleneck rocker arm stud unlike Chevrolet. There is no adjustment. The rocker arm nut is torqued to 30 ft/lbs.

 

[Steweyfan]

Oh wow! That is interesting and kind of makes sense as to what I'm seeing and dealing with. I will test that out, I'm still not 100% sure if it hasn't been changed or modified but at least I have a direction and more of an understanding as to what I'm dealing with....thank you for your input.

So it doesnt matter what position the vavles are tdc etc when i torque the rocker arms as long as it is 30lbs?

 

[melsg5]

Oh wow! That is interesting and kind of makes sense as to what I'm seeing and dealing with. I will test that out, I'm still not 100% sure if it hasn't been changed or modified but at least I have a direction and more of an understanding as to what I'm dealing with....thank you for your input.

So it doesnt matter what position the vavles are tdc etc when i torque the rocker arms as long as it is 30lbs?

Correct, the bottleneck stud places the lifter at its correct clearance. But why do you even have to do that, they don't loosen by themselves.

______________________________

 

[Steweyfan]

Lol... that's a good question
I loosened a couple when thinking I had hydraulic lifters, while it was warmed up and running. Then realizing that I wasn't hearing any clatter like they did when they loosen up a little. So I stopped and tried to get them back close to where I thought they were. I researched and didn't find this info anywhere.
Mind you, it's been probably 30 years since owning a Pontiac and I was in my early 20's and I didn't own it very long. I have mostly owned chevy's and still own a 63 Nova. It's been fun learning Pontiac stuff and I'm surprised how much different they are to standard Chevy components.
It's been a fun journey so far and I'm looking forward to learning more.
Thanks again for your input.

 

[melsg5]

Lol... that's a good question
I loosened a couple when thinking I had hydraulic lifters, while it was warmed up and running. Then realizing that I wasn't hearing any clatter like they did when they loosen up a little. So I stopped and tried to get them back close to where I thought they were. I researched and didn't find this info anywhere.
Mind you, it's been probably 30 years since owning a Pontiac and I was in my early 20's and I didn't own it very long. I have mostly owned chevy's and still own a 63 Nova. It's been fun learning Pontiac stuff and I'm surprised how much different they are to standard Chevy components.
It's been a fun journey so far and I'm looking forward to learning more.
Thanks again for your input.

Ok, then just retigthen them to 30.