Solid lifter initial valve lash adjustment

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340inabbody

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so I have read how to set solid lifter valve lash hot. But on an initial set up how to you set the lash cold before the first fire to get them close? Is it the same method as hot then tweak them in after the engine gets to operating temp?
 
Yes, same method with slightly more clearance to allow for thermal expansion of the valve components. Most lash specs list hot/cold values. 65'
 
Adjust with what the lash is supposed to be. After you break it in, check them again. The lash will open up roughly.005 from cold to hot.
 
@toolmanmike can maybe find the most recent thread where this came up and post a link to it.

The upshot is for cold settings with an iron block and heads start your lash .003-.004 TIGHT.

If you have aluminum heads and an iron block set your cold lash at .006-.008 TIGHT.

For an all aluminum engine set the lash .014-.016 TIGHT.

Once the engine is warm check the lash and see where it is hot. If the hot lash doesn’t match what it should be (let’s say you want a .020 hot lash so you set them at .016 and that .016 is now .022 hot you know you need to set the cold lash .002 tighter cold to end up with the correct hot lash) then adjust the cold lash accordingly.

I never ever try to set the valves hot. I set them cold. Then I check a couple of random valves to see where I’m at hot and make the corrections cold.
 
so I have read how to set solid lifter valve lash hot. But on an initial set up how to you set the lash cold before the first fire to get them close? Is it the same method as hot then tweak them in after the engine gets to operating temp?
My engine has a 276/286/110 cam and hydraulic lifters, and was initially set-up at 1/4 turn preload. This quickly proved to be inadequate, as soon after break-in it began to tick. I reset the preload to 1/2 a turn. And so it was quiet for a long time.
Eventually, I got the idea that if I ran the Hydros at zero-preload, they would act like solids, so I set them that way. Now they tick ever so slightly.
The result of this is that the lifters cannot pump up, if the springs lose control; and so, the engine revs to over8000 on a miss-shift, lol. So I installed a rev-limiter, then fixed my shifter. 7200 is all she gets now.
That was 20 years ago. and she still ticks a lil.

Another upshot of this, is that since the lifters cannot pump up, which could drive the valves into the pistons, I no longer have to worry about that.
The Exhaust valves, in particular, need some seat time to transfer heat to the head. And so, in my case, the exhaust valves get at least the maximum amount of seat-time allowed by the cam.
IMO
On the street, a lil loose is better than a lil tight.
 
I set my hydraulic roller as if it were a solid.
 
I set the lash a .020” cold and after a break in cycle the lash was .022”-.024” hot. R3 block with W9 heads. this is a roller cam but i do the same with SFT.

IMG_0738.png
 
My engine has a 276/286/110 cam and hydraulic lifters, and was initially set-up at 1/4 turn preload. This quickly proved to be inadequate, as soon after break-in it began to tick. I reset the preload to 1/2 a turn. And so it was quiet for a long time.
Eventually, I got the idea that if I ran the Hydros at zero-preload, they would act like solids, so I set them that way. Now they tick ever so slightly.
The result of this is that the lifters cannot pump up, if the springs lose control; and so, the engine revs to over8000 on a miss-shift, lol. So I installed a rev-limiter, then fixed my shifter. 7200 is all she gets now.
That was 20 years ago. and she still ticks a lil.

Another upshot of this, is that since the lifters cannot pump up, which could drive the valves into the pistons, I no longer have to worry about that.
The Exhaust valves, in particular, need some seat time to transfer heat to the head. And so, in my case, the exhaust valves get at least the maximum amount of seat-time allowed by the cam.
IMO
On the street, a lil loose is better than a lil tight.
Are we talking about hydraulic or solids? My solids on my 273 are loose and rattle a bit when cold. They quiet down when the engine gets warm.
 
It doesn't matter, he should go with what they ask for. After break in or driving around for a week end, he should recheck them. Solids should be checked periodically, as should hyd's. It doesn't matter, really, .002 to .005 won't kill anything if it's off, that's why we recheck things. Move on
 
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