How tight to set solid lifters

[toolmanmike]

That makes no sense Mike. The heads and block grow with heat. Just like with aluminum heads but not as much.

Edit: I always forget to mention engine temp matters. And engine at 160 degrees won’t grow as much as an engine running at 195-200.

You have to check hot lash at the temp you are going to run.

Think about it this way, If the valvetrain wouldn't expand with heat, there would be no reason for valve to rocker clearance. The way you are thinking, you could set them at zero and have no issues. The lash (clearance) is to make up for expansion at operating temperatures.

 

[Newbomb Turk]

Think about it this way, If the valvetrain wouldn't expand with heat, there would be no reason for valve to rocker clearance. The way you are thinking, you could set them at zero and have no issues. The lash (clearance) is to make up for expansion at operating temperatures.

I get that. But, you can’t set the valves with zero lash cold because the valves will grow faster than the heads and block. Then the valves will be open and you won’t have compression.

And ambient temperature matters. Check lash at say, 30 degrees and check it again at 100 and see what you get. That’s why there has to be some lash to compensate for cold starts.

When I put my engine on the dyno I will make a video of lash changes. I would hope that would put this to bed, but it won’t.

Thats why running solid rollers on a hydraulic roller lobe is touchy. If you set them at say .004 cold on an 80 degree day and then try to start the engine on a 30 degree day you’ll likely have at least one cylinder that won’t hit because the valves are open.

 

[toolmanmike]

I get that. But, you can’t set the valves with zero lash cold because the valves will grow faster than the heads and block. Then the valves will be open and you won’t have compression.

And ambient temperature matters. Check lash at say, 30 degrees and check it again at 100 and see what you get. That’s why there has to be some lash to compensate for cold starts.

When I put my engine on the dyno I will make a video of lash changes. I would hope that would put this to bed, but it won’t.

Thats why running solid rollers on a hydraulic roller lobe is touchy. If you set them at say .004 cold on an 80 degree day and then try to start the engine on a 30 degree day you’ll likely have at least one cylinder that won’t hit because the valves are open.

Weren't we talking about setting lash cold by adding a couple thousands to make up for the expansion with heat? Setting them hot takes the expansion out of the picture.

 

[Newbomb Turk]

Weren't we talking about setting lash cold by adding a couple thousands to make up for the expansion with heat?

That’s what some of you are saying. I heard that myth years and years ago that an engine with iron heads and block you needed to set the cold lash .002-.004 LOOSE cold. If you do that, when you get to operating temperature the lash will be looser than what you want.

Any engine when started will have the valves grow (take up some lash) when they first start because they see all the combustion heat. The block and heads don’t grow as fast because of the amount of mass you’re heating. Plus the coolant.

So yeah, they may get a bit quieter on start up with some heat but when everything is hot the lash will be looser than what you were shooting for.

 

[pittsburghracer]

I’m out of this one after this but there’s some very wrong posts being made here.


Rule of thumb is to set cold lash 4 thousandths smaller than hot lash. Valve clearance increases when hot, 100%. If the valve cover is easy to remove check it and reset if necessary after it is warm. on an iron head yes.

 

[4spdragtop]

That's what Comp told me as well when we were redoing the top end. Hotter means wider clearances...had me scratching my head, but what do I know lol.

I’m out of this one after this but there’s some very wrong posts being made here.


Rule of thumb is to set cold lash 4 thousandths smaller than hot lash. Valve clearance increases when hot, 100%. If the valve cover is easy to remove check it and reset if necessary after it is warm. on an iron head yes.

 

[toolmanmike]

That's what Comp told me as well when we were redoing the top end. Hotter means wider clearances...had me scratching my head, but what do I know lol.

If I remember it this spring, I'll set mine cold and check them hot and record the results. Mine are always loose when cold (slight clatter) and quiet down (lash tightens) when hot.

 

[Dave999]

Mine clatter when cold and hot
the sound changes as the motor heats up

its a feature of my engine
this is a reason the Australians call them rattlies
they rattle a bit with Hydraulic lifters they rattle more with solid

BUT i set them as the cam card said 20 thou on both, cold.
i even approach this by winding engine forward and back wards to take out any twist and flex in my long cam
Its still a noisy rattly bastard

how do you come up with a setting for a motor that always had hydraulic lifters that were preloaded mostly the same as a 318 would be, can't remember 40 60 or 80 thou that now has solid lifters and adjustable rockers

can't help feeling the cam grinder just picked "safe"

i should try setting them hot. if its good enough for a slant 6 it should be good enough for its younger brother...

when its not freezing or raining or both

id expect the pushrods to get longer slightly
ide expect the valve to get longer slightly
but id also expect the block to get taller slightly
and the head to get thicker slightly

do i end up back where i started?
none of this mattered with hydraulic lifters would standard pushrods expand more then nice new clay smith pushrods ?
if i chop 60 thou off the head does it expand less due to less metal more due to less mass

aaaaaaargh
etc

Dave

 

[mopardude318]

Can someone refresh my memory..the 4 position method of adjustment. Would that be rotating the engine every 90 degrees and adjusting 4 valves? 2exh/2int on the opposing cylinders?

 

[Newbomb Turk]

Can someone refresh my memory..the 4 position method of adjustment. Would that be rotating the engine every 90 degrees and adjusting 4 valves? 2exh/2int on the opposing cylinders?

Yes. But when you get over about 280 degrees of seat timing the 4 position method isn’t as accurate. BTDT

 

[fishmens67]

Adjust them engine hot and running.

Feeler gauge in.. snug and lock down.

This is a concept hard for some to comprehend.
The constant voodoo magic is the cause of most failures.
Set it cold once on initial start

 

[fishmens67]

I’m at .012 on my stock 360 block and Edelbrock heads. I’m at .008 on my aluminum keith black block and aluminum heads. Make sure you get some heat in that sucker before you heavy foot the accelerator

This has worked for over 50 years

 

[66fs]

LOL I'm done.

Just because I'm done, does not mean you are right. I'm done arguing.

 

[fishmens67]

Just because I'm done, does not mean you are right. I'm done arguing.

Who's arguing. always check them hot, don't assume expansion will be even on all sixteen valves.

 

[66fs]

Who's arguing. always check them hot, don't assume expansion will be even on all sixteen valves.

Can't argue with that. But not a reply to you.

 

[Newbomb Turk]

Can't argue with that. But not a reply to you.

That was for me Fishmen. I’ll say it again. No one, and I mean NO ONE that isn’t running stock junk is setting their valves with the engine running.

I said post a video. I want to see it. But that’s not going to happen.

 

[Newbomb Turk]

Who's arguing. always check them hot, don't assume expansion will be even on all sixteen valves.

See post 41.

 

[Mopar69gts]

For what it's worth,
I'm building a bbc with a Howard's Solid Roller and I called them today about setting the lash for initial start up
The Hot setting is .022 for both valves
He said to set them .018 cold
Then check again when Hot, the lash will grow about .004 when Hot on a iron block with aluminum heads.
Straight from Howard's Cams...

 

[66fs]

That was for me Fishmen. I’ll say it again. No one, and I mean NO ONE that isn’t running stock junk is setting their valves with the engine running.

I said post a video. I want to see it. But that’s not going to happen.

We are talking stock junk parts for sure. You could not do it anyway.

 

[MOPAROFFICIAL]

However you end up adjusting them just make sure it's hot and that the exhaust valve is fully open when adjusting the intake and vice versa

 

[66fs]

That was for me Fishmen. I’ll say it again. No one, and I mean NO ONE that isn’t running stock junk is setting their valves with the engine running.

I said post a video. I want to see it. But that’s not going to happen.

Next time I'm due to readjust the valves, I'll post a video for those who can't figure it out. The 273 is at 10,000 miles now, next adjustment is at 100,000 mile. This is not racing garbage.

 

[66 Sat]

This was one of the articles I read that lead me to setting them a tad wider:
“What I Learned Today” With Jeff Smith — Cold Lash Vs. Hot Lash

From the article:

Thermal Expansion Table​

Because the engine dimensions will change with the heat of operating temperature, Crane Cams came up with a chart that we’ve reproduced here that compensates for cold lash settings compared to the published specs for an engine fully warmed up:

Block Material	Head Material	Lash Adjustment
Iron	Iron	Add 0.002”
Iron	Aluminum	Subtract 0.006”
Aluminum	Aluminum	Subtract 0.012”

This article from Motortrend had slightly different advice but a similar theme:
https://www.motortrend.com/how-to/1707-how-to-set-valve-lash/#:~:text=Generally speaking, if you are running an engine,of an inch tighter than your hot number.

This is a repeat of the top article, with Crane Cams again as the source:
Rockin’ The Lash: Setting Valves Cold With Hot Lash Settings

Hopefully I'll do my own measurements hot vs cold very soon so I can confirm who is correct.

 

[Bewy]

Post #35. Incorrect. The 4 position method is very accurate up to 290* at 050, not 280* of seat timing. More than 290, the 8 position is more accurate. It is on p.306 of my MP book.

 

[Bewy]

66 Sat.
Do the simple procedure that I outlined in post #12 to see the hot/cold lash difference for your engine. Then adjust accordingly.
Loosening the lash will usually smooth the low end because you are reducing duration & overlap.

 

[Bewy]

One reason for hot/cold differences for all iron engines is valve material. Many aftermarket valves are made of stainless steel, which has about 1.5 times greater expansion than steel.