How tight to set solid lifters

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Texas Red

Texas Red

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It probably has been asked before but let's review the age old question of how tight should the gap be on setting solid lift gap. Clay smith cams tells me 018 thousands! After watching an episode of Power Nation Pat Topolinski states that changes if you are running aluminum heads on a cast iron block (Yes I am) He stated it should be tightened up by about .004 which will put me at .014. So not to cause myself any problems I need to ask what are you running/ setting yours at.
My set up.
Caly Smith flat tappet cam
American made lifer's (From them)
Smith brothers push rods
Harland Sharp 1.6 roller rockers

Set mine at .018 for start up using the E.O.I.C. method which might be controverisal all in its self .... I dont want to start any big debate like what kind of oil do you run......
No I have not done the hot setting ....
Please advise Texas Red
 
Iron heads/iron block .002-.004 tight
Aluminum heads/iron block .006-.010 tight
Aluminum heads/Aluminum block .012-.020 tighter

Thats where I start. The only way to know is get it hot and check them and adjust your cold lash to match.
 
I found ,with alu heads and cast block, the gap needed to be opened up that much more. I did the 004 to 006 tighter and when the engine was warm I had no lash. I had a leaking valve cover gasket and had to pull the cover. Checked the lash....nothing.
 
The cam card will tell ya where they suggest, the 408 in my Valiant are at .020, been about 5 years, no problem, RHS iron heads.
 
66Valiant528 said:
I found ,with alu heads and cast block, the gap needed to be opened up that much more. I did the 004 to 006 tighter and when the engine was warm I had no lash. I had a leaking valve cover gasket and had to pull the cover. Checked the lash....nothing.
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And that’s something that makes doing lash a bit harder and that is even the same castings won’t always change dimensionally the same. They are castings so even though they may look identical they can vary.

Even billet heads and blocks don’t all change the same even at the same temperature increase.

I sounds like the OP did the lash correctly other than I don’t know if he went tight enough. He just has to verify that when hot.

The other thing I forgot to mention is that some say with iron you set the lash LOOSER when cold. Never have I seen that. Even an iron/iron deal gains lash when it heats up.

For those of you that go to drag races if you are there with blown alcohol cars you should watch them warm up.


Keep an eye on the blower belt. That thing will be flopping around like a wet noodle when they first fire off, but in about 2 minutes you’ll see the belt slowly tighten up.

Thats how much they can grow.
 
Isn't the issue that the valves expand when hot and clearance diminishes? The lash gets tighter when hot. Add the 005 to your lash cold. At least this has worked for my Edelbrock cast 452 aluminum heads on my 440.

20231005_161329.jpg
 
66Valiant528 said:
I found ,with alu heads and cast block, the gap needed to be opened up that much more. I did the 004 to 006 tighter and when the engine was warm I had no lash. I had a leaking valve cover gasket and had to pull the cover. Checked the lash....nothing.
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After switch to alloy: Yup, I had a couple black/wet plugs and oily cylinder. Reset valves 005 looser and problem solved
 
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
 
I would call Clay Smith. Some lobes are more friendly than others as far as varying the predetermined valve lash by very much.
 
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Just expanding on what NBT said in post #2.
Set at about 018-020 as a starting point, not critical, but make a note of what you start with. Have tools, feeler gauges ready for quick valve cover removal. Get engine to operating temp & QUICKLY remove a valve cover while hot. Find a loose rocker, measure the lash & record it. Leave overnight & measure the lash again when cold. The difference is your hot/cold setting. I always lash sol lifter cams pretty tight, about 012-015 at operating temp. It does not do any harm & the valve train is quieter; also, it leaves more of the lash ramp to absorb the inertia of the valvetrain.
Rocker shaft engines like the SBM & BBM will probably have a slightly greater hot/cold [ .001" - 0.003" ] difference than a SB Chebby that uses a rocker stud. This is because the stand for rocker shafts is alum [ more expansion than steel ], whereas the stud is steel.

The EOIC method is a lot time wasting wrenching when the 4 position method is much easier.
 
Well I'm confused. I did this job on my poly 2 weeks back. The lash adjusters don't have a lock nut, they are an interference fit and one was loose. I pulled the valve cover due to the ticking noise and discovered it backed right off, so I thought I'd check them all.
First time I've ever done it and I used the EOIC method which worked fine. But I was unsure of the cold vs hot measurements so started researching.
From what I found I thought iron to iron you set looser when cold. The cam card says .014 on exhaust and intake so I set them all to .016. They were all around that anyway, except the one that was loose obviously. The car runs super smooth with them at this looser cold setting.
The only way to confirm it is to pull a valve cover and remeasure when hot as suggested.
I'm intrigued now as to which is correct, I might try this tomorrow and report my findings.
20240115_152642.jpg
 
Keep tightening them up and test driving until the valves hit the pistons, then back off a little after you blow up the engine....
 
With cast iron heads set your cold lash .002 looser on initial start up. Then hot and running per card, see post #9. That being said, I have set a lot different cams at .013 intake and .021 exhaust hot and running.
 
Big Daddy Mopar...Larry Callahan of Callahan's repair shop in the little town of Sheldon Illinois had me cut the tops out of an old set of 273 valve covers so they could bet set thru the top hot. Then when everything was set pop the original covers on with the fresh gaskets. Valve covers were a dime a dozen back then...LOL
 
66 Sat said:
Well I'm confused. I did this job on my poly 2 weeks back. The lash adjusters don't have a lock nut, they are an interference fit and one was loose. I pulled the valve cover due to the ticking noise and discovered it backed right off, so I thought I'd check them all.
First time I've ever done it and I used the EOIC method which worked fine. But I was unsure of the cold vs hot measurements so started researching.
From what I found I thought iron to iron you set looser when cold. The cam card says .014 on exhaust and intake so I set them all to .016. They were all around that anyway, except the one that was loose obviously. The car runs super smooth with them at this looser cold setting.
The only way to confirm it is to pull a valve cover and remeasure when hot as suggested.
I'm intrigued now as to which is correct, I might try this tomorrow and report my findings.
View attachment 1716197180
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I’ll say it again. I have never, ever seen an iron/iron combination need LOOSER lash cold. Ever.

Thats another stupid myth that won’t die. Iron grows when heated Just like aluminum. It just doesn’t grow as much.

Check it for yourself. Set them loose cold, get it hot and see where they are. Then you will know for sure.
 
Newbomb Turk said:
I’ll say it again. I have never, ever seen an iron/iron combination need LOOSER lash cold. Ever.

Thats another stupid myth that won’t die. Iron grows when heated Just like aluminum. It just doesn’t grow as much.

Check it for yourself. Set them loose cold, get it hot and see where they are. Then you will know for sure.
Click to expand...

Been doing 50 years. Not in my experience. I check everything so close you can not imagine.
 
66fs said:
Do you check them hot and running?
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Nope. Post a video of you doing it. There is no way you can accurately set the valves with the engine running.

And, I’ve never ever seen a Pro Stock engine that had the valves set with the engine running. If anyone was going to do it, it would be them.

There is no way you can hold the wrench, work the feeler gauge and get the **** right and tight with the engine running, unless you let the engine run at 200 RPM. And I would never do that.
 
Newbomb Turk said:
Nope. Post a video of you doing it. There is no way you can accurately set the valves with the engine running.

And, I’ve never ever seen a Pro Stock engine that had the valves set with the engine running. If anyone was going to do it, it would be them.

There is no way you can hold the wrench, work the feeler gauge and get the **** right and tight with the engine running, unless you let the engine run at 200 RPM. And I would never do that.
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LOL I'm done.
 
Newbomb Turk said:
I’ll say it again. I have never, ever seen an iron/iron combination need LOOSER lash cold. Ever.

Thats another stupid myth that won’t die. Iron grows when heated Just like aluminum. It just doesn’t grow as much.

Check it for yourself. Set them loose cold, get it hot and see where they are. Then you will know for sure.
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Of course they are looser cold. Start a engine up cold and the solids clatter. As the engine warms up, the lash tightens and the clatter goes away. Yes, they need to be a little looser if you adjust them cold.
 
toolmanmike said:
Of course they are looser cold. Start a engine up cold and the solids clatter. As the engine warms up, the lash tightens and the clatter goes away. Yes, they need to be a little looser if you adjust them cold.
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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.
 
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