Adjust Solid Valves

ROYALOAK62

Well Known Member
Supporting Member 1
#1
Was bench racing the other day. (Car talk with friends)

Someone said you can adjust solid valves to spec's with the plugs out. His engine dosen't have them. This went around and around.
I was with the you can't do it side.:nono1:
Is it possible with no compression?:scratch

Lets hear from the experts on this.

Dave
 

Skip FIx

Well Known Member
#2
It's easier to spin with no plugs in , but using the starter sometimes it bumps over too much.

Set exhaust valve as intake closes, set intake as exhaust opens.
 

dq409

Well Known Member
Supporting Member 3
#3
Compression has nothing to do with setting the valve lash.
The valve train doesn`t know or care if there are any spark plug !!

The valves are opened and closed by the push rods riding on the lifters riding on the lobes of the cam .The cam is rotated by the crank. ,,dq
 

SS425HP

Well Known Member
Supporting Member 3
#4
Lash setting, hot and cold.

Now we have a good discussion going. I used to set my valves .002 wider when cold. The guy I have been working with says that when everything heats up, the lash opens up. He sets his valves about .004 closer when cold. My cam calls for .030 hot, he sets them at .026 cold. Says they will be about right on at temperature. Who is right? Haven't checked them hot after setting them cold. Don't like setting valves hot. Seem to get burnt!!!!!!!!!!
 

Fathead Racing

Well Known Member
Supporting Member 7
#5
I have set Hydro/solid flat tappet solid roller hot cold, plugs in plugs out. My favorite is with the intake removed and the engine hanging on the stand. :beerbang
 

dq409

Well Known Member
Supporting Member 3
#6
I set mine cold,,, My builder says no big deal !!

Runs great when running so I guess so,,

I have several friends that set theirs while the engine is running !!!
 

ROYALOAK62

Well Known Member
Supporting Member 1
#7
I guess I must not of been thinking clearly that night. Thanks for setting me straight. It was a loooong night. I do like Fred's note about not being burnt.

Dave
 

skipxt4

Well Seasoned Member
Supporting Member 13
#8
Solids

ROYALOAK62; I'm sorry. I gave you the wrong info. I'f you're setting the valves Cold, subtract .002- .004 from lash settings. eg: .030 minus .002 equals .028. Fred, you were positively correct. Just another case of not engaging brain, before opening mouth. (Its called being 59). You're right about getting burned, not only that, setting the valves HOT usually coats your fenders, hedders, and your shirt with hot oil. Skip :eek:
 

SSpev

Well Known Member
Supporting Member 3
#9
About 10 years ago, this was checked on a heavy duty natual gas engine. Set the valves cold, room temp. Run the thing till it was HOT. 260 oil temp. 2 people pulled it apart, HOT, as fast as you can and measured the lash...... there was NO difference. Yes, the lash will change with heat, but you can't check them fast enough before it cools enough to go back to nominal. You should just set them cold.
 

tripowerguy

Well Known Member
Supporting Member 3
#10
Back in 58 we always set the valves with the engine warmed up and running. The key is having clips on all the rocker arms that stop the oil from squirting out . This stopped all the oil on fenders ,you and no burns. I still have them in my tool box. I have poly locks on my rocker arms now and I have not had one valve out of adjustment in 2 years.:clap Roy
 

raymar58409

Well Known Member
Supporting Member 2
#11
Roy

I got I think 7 of then left on the shower curtain hook. Seems the cams I used to run used to flip em off into space somewhere out near Pluto never to be seen again. This action was then followed by the exiting burning, staining, brown fluid.

But seriously, the difference in the lash settings between hot and cold is due to the expansion of the block, heads, pushrods. In an all iron engine it's slight, but all you guys with all the money to have aluminum headed "w"engines would notice a greater difference as aluminum expands at something like .007 per inch.
The old Beetle engines were easy to check hot against cold cuz you only had to flip the wire retainers to get the rocker covers off. For you youngsters they had retainers like brake master cylinders, wait, they'd be to young to remember those to maybe.:dunno
Ray
 

mpris

Well Known Member
Supporting Member 2
#12
I stopped by a friend of mine who builds race engines for a living. I have watched him assemble hundreds of engines and he sets the valves cold while still on the engine stand. He sets them at the correct lash for the cam. Today when I got to his shop he had an engine on the dyno and had just completed about 5 runs. He then pulled the valve covers and ran back through the valves and I ask how much the settings changed after the engine got hot. Supprisingly he said that on an aluminum head engine they usually loosen 4 to 5 thousands and on cast heads they usually tighten up 2 thousands. So I would say if you want to adjust them exact, without a mess, get the engine hot and run through them without the engine running by bumping the starter. Thats how he does it on the dyno.

Poocho
 
#13
I have also found this to be true

It seems to me that the difference between hot and cold is only a few thousanths on an already broken in cam. I have run the "30/30" Duntov cam for years and set mine at .018 cold on TDC for each cylinder. TDC is not the base circle for the cam but the difference is such that the actual lash on the base circle will be .024 (each cam will be different according to profile of clearance ramps- just set them properly on the base circle first and then measure to see how much tighter they will be on TDC) and then when it warms up it opens up to about .025+-.001. This method is quite useful if you need to make quick checks at the track or have more valuable use for your time than leaning over fenders checking lash settings. The one or two thousandths error here is very difficult to measure at best. I doubt anyone can make it perfect. It is even harder to believe anyone could measure the difference in performance from one or two thousandths anyway.

Just my two cents.

Henry
 

Dond409

 
Supporting Member 1
#14
you would be surprised!!!!!!!!!!!!

I usually check lash at the track. Depending on air conditions I will adjust valves accordingly. In good air I loosen up the intakes .004. In bad hot air I tighten up the intakes and exhaust .002. It does make more of a difference than you would think.
 
#15
At the track

It seems to me that our track is prepped so inconsistently that we have a tough time telling what makes a difference. I have noticed some nights the track is prepped very well and the car hooks very hard to the point it almost wants to bog on take-off and other nights the tires spin. I usually have to adjust tire preasure up and down as well as burnout time.

I have though noticed the following differences on a 6500-7000 rpm street engine with unported bowtie heads: The better performer is listed 2nd

Performer rpm vs old style Torker: 0.05sec
Victor Jr vs old Turantula: 0.08sec on TH350 2800 stall setup
A wash on the stick shift
Torker vs Turantula: 0.1sec .05 on auto

get this: on 350 engine same as above- TH350 2800 stall 3.50 -4.11 gears 0.10sec.

this is a best effort to tell the differences at the track, due to much variation at the starting line. Now that you mention lash though, The only time I was able to get a 12.82 out of the automatic setup was lashed .008 tighter than I usually ran with the stick shift.
 

dq409

Well Known Member
Supporting Member 3
#16
Dond409 said:
I usually check lash at the track. Depending on air conditions I will adjust valves accordingly. In good air I loosen up the intakes .004. In bad hot air I tighten up the intakes and exhaust .002. It does make more of a difference than you would think.
I think if I get this right,,, been a while since I`ve thought about car engines,,,,

Tighter will give more to the lower end,,, looser more to the top end,,,
just like a cheat in cam timing,,,dq
 

dq409

Well Known Member
Supporting Member 3
#17
Also,,,, ever watched how other people set their lash??

Everyone does it a tad different.
Some like the feeler gauge to have to be pulled out tight,
others prefer to have them just snug.

I think the best way to do it is to just be consistant on all valves,,,no matter how you do it,,,

Only a few of us are looking for that extra 100 of a second extra in their ET,,,

Most would never notice the difference between a few thousands in lash,,, JMO,,dq
 

Ronnie Russell

Well Known Member
Supporting Member 2
#18
Jim, In my opinion, your last post was perfect. I couldnt have made those points any better. ( No surprise, cause I dont talk very good) Good job. :cheers :cheers
 

ROYALOAK62

Well Known Member
Supporting Member 1
#19
dq409 said:
Also,,,, ever watched how other people set their lash??

Everyone does it a tad different.
Some like the feeler gauge to have to be pulled out tight,
others prefer to have them just snug.

I think the best way to do it is to just be consistant on all valves,,,no matter how you do it,,,

Only a few of us are looking for that extra 100 of a second extra in their ET,,,

Most would never notice the difference between a few thousands in lash,,, JMO,,dq
So far thanks for all the replys. I like to do on things the easy side so I'll remove the plugs and adjust the valves cold. Plus I'm not a racer but a cruiser.

I do have one other question.

I know the following.
64 block by the code stamped on the block
690 heads
2-4 carbs
700R4 trans
4:11 posi rear
I do not know what cam I have, sorry

QUESTION
What adjustment spec's should I use?
Bob's list shows 1962 (I) @ .008 (hot) & (E) @ .018 (hot)

For 1964 the list shows (I) .018 (hot) & (E) @ .030 (hot)

Dave
 

dq409

Well Known Member
Supporting Member 3
#20
ROYALOAK62 said:
QUESTION
What adjustment spec's should I use?
Bob's list shows 1962 (I) @ .008 (hot) & (E) @ .018 (hot)

For 1964 the list shows (I) .018 (hot) & (E) @ .030 (hot)

Dave
Man,,, Every cam is different !!! I ain`t touching this one,,,
 
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