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Sox
04-06-2008, 02:31 PM
Does anybody know the sequence for adjusting valves.Im used to doing each cylinder at a time.Years ago a guy told me an easier way by bringing number 1 tdc on the compression stroke doing 8 valves spin the motor 360 and doing 8 more.Does anybody know that sequence. This is suppose to help keep the lube on the lobes of the cam when putting together a new engine by only spinning the motor 1 time.Any help would be great..

mark6052
04-06-2008, 09:03 PM
most manuals, like chiltons, has the sequence posted. BUT its for solids. and it wont work for large aftermarket race cams. best is to do each at tdc. or better is the adj intake when exht starts to open, do exht when intake starts to close. I checked on my hemi there is about .002 diff between them. its what works for me. I assume this is on older style v8s. newer hyd cam engines are way diff.

fishman1
04-07-2008, 06:26 PM
With the engine in the #1 firing position, following valves can be adjusted
exhaust 1,3,4,8
intake 1,2,5,7

turn engine over 360 degrees adjust following valves

exhaust 2,5,6,7
intake 3,4,6,8

olds48
04-07-2008, 07:29 PM
Hey Fishman,does that work with a cam with alot of duration,too??Always curious about that :?: :?:

fishman1
04-08-2008, 12:46 AM
Hey Fishman,does that work with a cam with alot of duration,too??Always curious about that :?: :?:

I am going to try it at the dyno on friday and see the diffrence

Tod74
04-08-2008, 04:06 AM
With the engine in the #1 firing position, following valves can be adjusted
exhaust 1,3,4,8
intake 1,2,5,7

turn engine over 360 degrees adjust following valves

exhaust 2,5,6,7
intake 3,4,6,8

Wouldn't that depend on the firing order? How can that work on every engine if the firing orders aren't the same?

Unless "1 2 3 4 " doesn't neccesarily mean cylinder number "1 2 3 4 " but rather the cylinder that fires 1st Then the cylinder that fires 2nd etc

What am I not understanding?

suicidebomb
04-08-2008, 04:40 AM
Looks to me like no matter what, you have to turn the crankshaft 720*, so whats the advantage? If you still have turn the motor over twice what difference would make, as long as you adjust the valve on the base circle of the cam?
suicidebomb

Tod74
04-08-2008, 05:31 AM
Looks to me like no matter what, you have to turn the crankshaft 720*, so whats the advantage? If you still have turn the motor over twice what difference would make, as long as you adjust the valve on the base circle of the cam?
suicidebomb

How you figure ya need to turn it over 2 times? Do 8..then turn it over and do the other 8.

suicidebomb
04-08-2008, 06:20 AM
You're right, Too little thought, too much mouth. But... I still see little to no advantage to it,over adjusting each cylinder individually. You still have to adjust 16 valves, and its the adjusting that takes the time, not the turning over the motor. jmho Also unless the motor was shut off at top dead center compression stroke #1 or 6 cylinder you are going to have turn the motor to that before beginning anyway. I just don't get it, but I'm old and stuborn! :oops: And, if you're doing it to keep assembly lube on the cam lobes, wont most of it be wiped off by the time you get the valves adjusted anyway?

sg1586
04-08-2008, 07:34 AM
Here's the only way valves in a race motor should be adjusted:

When the exhaust valve is almost all the way open then adjust the intake on that cyd......

When the intake has fully opened and is about 1/2 way closed then adjust the exhaust on that cyd..

This is the way I have been doing it for years and never had a problem..

Good luck.. 8)

fishman1
04-08-2008, 03:42 PM
Here's the only way valves in a race motor should be adjusted:

When the exhaust valve is almost all the way open then adjust the intake on that cyd......

When the intake has fully opened and is about 1/2 way closed then adjust the exhaust on that cyd..

This is the way I have been doing it for years and never had a problem..

Good luck.. 8)

the question is why is it the only way, i have seen people post this is the only way but i see no reason why and i am ok with this is somebody tells me why, as far as setting them this way it is never exact as what 1/2 to you is diffrent to someone else and also how do u get it to half way exactly the same every time......the way i post is a eaxact way and if it is not the right way please inform me why

topcat572
04-08-2008, 04:18 PM
I agree with SG1586, this is the best way, especially with cams with a lot of duration. The old 90 degree way seemed to work for smaller duration cams.

olds48
04-08-2008, 04:21 PM
Maybe I'm over-simplifying it,but,when I set my valves I just simply bump the motor over til the valve I want closes and comes all the way up :? I know there is movement that the naked eye can't detect but the valve stays shut for some time during operatoin and I don't think that the window of opportunity to adjust the valve is all that narrow.If it's up,turn it a tad and if still no movement SET IT!!! :?: Maybe it's not as simple as I thought :(

fishman1
04-08-2008, 05:33 PM
Nobody has told me why it is the best way and the way i explained is the wrong way..i am getting opinions is all............i am going to the dyno on friday and i am going to try both ways to see what the diffrence is

olds48
04-08-2008, 07:20 PM
That'll be a good idea.Dyno's don't lie,do they!!I'm like you,just fishing for info.Let us know what you find out and have fun at the dyno!!

cepx111
04-08-2008, 08:09 PM
Here's the only way valves in a race motor should be adjusted:

When the exhaust valve is almost all the way open then adjust the intake on that cyd......

When the intake has fully opened and is about 1/2 way closed then adjust the exhaust on that cyd..

This is the way I have been doing it for years and never had a problem..

Good luck.. 8) Not trying to pick sides or anything but this is the way I've always done it. Now my buddy who has a "FORD" did it the way fishman does his with no issues, but then again he's not running a cam with 722 lift and 320 degrees of duration either.
Another thing I always do is install a remote starter switch on the firewall so I can bump the motor over while adjusting the valves, just makes it easier.
Charles

Tod74
04-08-2008, 10:56 PM
With the engine in the #1 firing position, following valves can be adjusted
exhaust 1,3,4,8
intake 1,2,5,7

turn engine over 360 degrees adjust following valves

exhaust 2,5,6,7
intake 3,4,6,8

Wouldn't that depend on the firing order? How can that work on every engine if the firing orders aren't the same?

Unless "1 2 3 4 " doesn't neccesarily mean cylinder number "1 2 3 4 " but rather the cylinder that fires 1st Then the cylinder that fires 2nd etc

What am I not understanding?

I am not arguing simply asking?

I do it the "eoic" way

fiveltretr
04-09-2008, 08:06 AM
I set valves the same way as fishman, I have read the replies from the guys that insist on the individual cylinder method, but they still have not answered fishmans question, why is your way correct. Opinions are not proof without some facts. I think fishmans point is at least his method is consistant every time, not, I think that valve is about 1/2 way down! With his method, you can simply change your valve lash ( with solid lifter cams) to experiment because the method itself never changes.

sg1586
04-09-2008, 04:26 PM
Go ahead and adjust the valves the way fishman said then rotate the crank back and forth a little at a time wile checking lash at every movement and you will see on "SOME" cyd buy doing it this way you won't be on the base circle of the cam all the time. Some may get tighter and some may be looser and some may be fine. It will have a lot to do with the duration of the cam.
Like I stated this is the way I do it and if I was working on your engine I would do it the same way and this way works for "any" engine..

Also If any of you go to a National Event go in the pits and you will see all the pro teams from Pro Stock to top fuel all do it the way I do :D ....

altune
04-09-2008, 10:49 PM
I was taught, this sequence by a very big engine builder.
intake vlave on its travel up to close, adjust exhaust on same cylinder.
when exhaust just drops, adjust intake on same cylinder. I have checked the adjustment at any other location say TDC and they always come up correct.
been doing it for 7 years that way

Cogburn
04-10-2008, 04:27 AM
Grab a cam and look at the lobes. That should tell you where you should set it. Some people like to pull each cylinder up to tdc and set valves but that will not be correct on many cams.

The EOIC (also KISS) method works because when the ex is opening the intake lifter is on the heel of the cam, and when the intake is closing the exhaust lifter is on the heel of the cam. No other method does that very well except maybe the one Crower has in the Crower book( I never really checked because the guys who race won't ever do it that way anyway).

You don't want to turn the engine over excessively because it is somewhat possible to start wiping a cam bearing from lack of lube and high spring pressure.

suicidebomb
04-10-2008, 04:56 AM
I'll be the first to admit I'm not very smart. So what cam, has a lifter on the opening ramp of the cam, on the compression stroke? Or what cam, does not have both valves completely closed at TDC on the compressiom stroke?

olds48
04-10-2008, 08:03 AM
I'll be the first to admit I'm not very smart. So what cam, has a lifter on the opening ramp of the cam, on the compression stroke? Or what cam, does not have both valves completely closed at TDC on the compressiom stroke?

I agree JMO

Cogburn
04-10-2008, 08:13 AM
There are a number of cams that will have a slightly different lash using the tdc method versus the EOIC method.

altune
04-10-2008, 06:44 PM
My bad,
exhaust should be almost entirely open,
intake should be almost closed.
dee de deee

rodsatheart
06-08-2008, 07:33 AM
Nobody has told me why it is the best way and the way i explained is the wrong way..i am getting opinions is all............i am going to the dyno on friday and i am going to try both ways to see what the diffrence is

Both methods are good, but the exhaust opening/intake closing is more accurate with large duration cams. The reason for not setting both valves at TDC is that the intake is still slightly on the closing ramp of the cam. I have seen as much as .015-.020 extra clearance on the intake with valves set this way and with Hyd. lifters will not center the plunger and not fully pump up resulting in lifter chatter.
The reason for the eo/ic method is it assures that lifter is on the true base circle of the cam and is highly recommended for large lift/duration cams. The reason is as the lift and duration increases the amount of available base circle decreases especially with flat tappet cams as the lifter requires a gentler ramp to keep the lifter off it's edges versus roller cams that don't require as much surface area and can utilize a faster more aggressive ramp and actually increase the amount of available base circle.
If you are going to use the TDC as fishman1 describes use the order for your engine as it needs to follow that particular firing order. If your curious if it is accurate for your cam go back and check with the eo/ic method and log any differences.

Here is a good article I found on this.
http://www.carcraft.com/techarticles/valve_lash/index.html

john858
06-08-2008, 12:39 PM
when you all figure it out let me know,i didn't know it was that hard sorry :oops:

bigs1975
06-08-2008, 01:56 PM
I'll be the first to admit I'm not very smart. So what cam, has a lifter on the opening ramp of the cam, on the compression stroke? Or what cam, does not have both valves completely closed at TDC on the compressiom stroke?
One thing not really mentioned is valve overlap.Thjats why large duratipon cams should be set EOIC.

rodsatheart
06-08-2008, 02:29 PM
when you all figure it out let me know,i didn't know it was that hard sorry :oops:
Sorry. Lets simplify it some.
Small lift/duration cams like Comps 270 & 280 are good to set using oem methods.
Large cams like Comps 292 & 305 series should be set using eo/ic method due to lobe overlap.
Hope that helps some.

prostreet1972
06-08-2008, 02:32 PM
That CarCraft Tech article pretty much sums it up. Even talks about dyno results. I can completely understand why the other type of adjusting (no. 1 TDC and no. 6 TDC) is just a rough one of adjusting.

Another question though. I have a Lunati bracket master cam that I am about to set the lash with. Should I just go with the lash on the spec card, or would it be safe to tighten it up .005-.010? I feel that my motor would like the little bit more lift.

rodsatheart
06-08-2008, 02:59 PM
I would just go with what's on the card. Probably wouldn't see enough gain to make it worth while.

bigs1975
06-09-2008, 10:59 AM
That CarCraft Tech article pretty much sums it up. Even talks about dyno results. I can completely understand why the other type of adjusting (no. 1 TDC and no. 6 TDC) is just a rough one of adjusting.

Another question though. I have a Lunati bracket master cam that I am about to set the lash with. Should I just go with the lash on the spec card, or would it be safe to tighten it up .005-.010? I feel that my motor would like the little bit more lift.

I've seen a few horsepower gain by doing this:Set the valves at the recommended setting on the cam card.Take a compression test reading on that cylinder.Tighten the lash up another .002 and take another compression reading.Keep doing this till you get the highest compression reading.But don't go more than .010 from the spec card.If it keeps getting higher compression readings after .008-.010 than you could probably use a little more cam.If the compression falls off than you have too much cam.

prostreet1972
06-09-2008, 04:04 PM
I am 24 and always a gearhead, but new to racing and trying to squeeze every horse out of a motor.

How does the lash make the compression go up? do valves close sooner on the compression stroke so it has more time to compress the gasses?

I just do that to one cylinder, then the rest would be the same, correct??

Also the cam card says that the center will make the cam 4* advanced. Does that mean that I need to install the cam 4* advanced?? Where do you think I will get the most power?

http://www.lunatipower.com/Product.aspx?id=1782&gid=245

It is strictly a drag car. Here is my set-up...third one up from bottom.

http://forums.racingjunk.com/viewtopic.php?t=2839&start=180

I apologize for jacking the thread a bit.

Thanks for the help...this site is great :D

bigs1975
06-10-2008, 07:36 PM
To tell you the truth I don't know how it changes but I know it works.True,You do it for every cylinder.
The cam card says it will be 4* advance if installed straight up.It just means the cam is ground 4* advanced on a straight up center line.Get the cam degree'd anyway to see if it lines up 4*.If not than you can have it dgree'd at 4* with the correct timing cain gear with the notches in it or set it up with a gear with adjustable bushings.Most good cam company's are dead on though.

Scooterz
06-14-2008, 09:15 AM
I just read this whole thing & it hurt my brain. I only have tried once w/ solid cam (lunatti) & set my intake & ex to.26. I used the remote start, & worked my way to each int/exh. It seemed to me that the duration/lash stayed the same once set... never picking up or loosing tolerance until lift came in to play. As a complete rookie, I hope I did this right. Here's my question- as long as my motor is setup this way, will the valve lash always remain the same? As it breaks in & wears, wouldn't the lash/tolerance change slightly over time?

Tod74
06-14-2008, 12:37 PM
If it is a solid roller it should not change. If it changes much you need to find out why. A roller lifter failure can and will destroy your whole engine.

cepx111
06-15-2008, 06:10 AM
I was told to set mine cold @ .022 all the way across even though the spec card says 28 and 30 hot. I talked with 2 guys I know that own their own racing engine service here in Memphis that used to do R&D for Joe Lunati and they recomended doing it that way.
They also said all that monkeying with tighter and looser valve lashes and using different ratio rockers trying to eck up an extra 1 or 1 1/2 hp is just plain horse hockey, there is just not that much hp to be made at the valve, better off spending that time and money else where in the motor. >Cp

olds48
06-18-2008, 12:52 PM
I agree with cepx.I set my solid rollers tight by .006" and usually works out purdy darn close

TheRabbit
06-18-2008, 02:05 PM
i set int. and ex. as tight as .017 cold. u don't need .024 of slop.
it's a safety / margin of error for a cam manufacture to give you.

FullTimeRacing
06-19-2008, 12:25 PM
so is there a best way for big(270@50)cams.I set mine @ tdc 1 at a time,and I'm joing to be checking it soon.I do it cold. :?:I have around 40 passes

FullTimeRacing
06-27-2008, 03:26 PM
after 40 passes pulled the valve covers to check the lash wow it was .030 started at .022 so i put on tdc.every rocker I could get a .018 gage under I adjusted.turned it 90* and so on.Did I do it right? All cold

burgessdg
06-29-2008, 07:27 PM
This is just an "opinion", but it is an opinion based on knowledge. Sure, there are more ways to skin a cat than just one. I don't remember reading if the question was directed at a hyd, or solid. Way different error factors there. You might not see any difference in the numbers on the Dyno with different syles of adjustment. But, the most foolproof way is to ensure the lobe is on the base circle of the cam. That takes the potential error of a high duration cam out of the picture with doing them on top dead center, or worse yet 8 at a time. I personally would never do 8 valves at a time on any cam with any duration. But hey, that's my opinion.

Dan

olds48
06-30-2008, 12:27 PM
after 40 passes pulled the valve covers to check the lash wow it was .030 started at .022 so i put on tdc.every rocker I could get a .018 gage under I adjusted.turned it 90* and so on.Did I do it right? All cold

You set them cold,did you check them cold or hot?The way you did it will work fine.Same way I do mine,with no problems.After you set them cold just go back and do one head at a time at operating temp.Do one head,fire the motor,get it back up to temp,then do that head.Checked mine this weekend after 30+ passes,intakes were dead on the money,ea few of the exhausts were about.003 loose.Just reset them hot and you'll be fine.Leaving them set where you set them cold is were your difference come from,probably,if not figure out why they are loosening.If you don't have stud girdles already ,they will keep them from backing off :D

Tod74
06-30-2008, 01:49 PM
They will be looser hot than cold. Mine is around .006 looser when hot. I just set mine cold that much tighter than I want them to be hot.

FullTimeRacing
07-01-2008, 08:40 AM
I allways set'em cold i don't like hot oil and stuff.Oh I have a stud griddle on it.

FullTimeRacing
07-02-2008, 06:12 PM
They will be looser hot than cold. Mine is around .006 looser when hot. I just set mine cold that much tighter than I want them to be hot.
I thought that it would be opozit(I know i did not spell that right)learned something new. :o

TheRabbit
07-02-2008, 06:51 PM
They will be looser hot than cold. Mine is around .006 looser when hot. I just set mine cold that much tighter than I want them to be hot.
I thought that it would be opozit(I know i did not spell that right)learned something new. :o

took me a minit to figure that out. my tired brain just wouldn't compute that for some reason!! lol

Thunder71
07-25-2008, 05:03 AM
i set mine> exhaust starts to open adjust intake on that cylinder>>>intake starts to open then to full lift then almost closed adjust exhaust...i warm motor to 160 degrees do 1 side then put valve cover back on then warm to 160 degrees then do the other side...i pull the plugs on the side i am doing so the motor turns easy with long rachet on the crank bolt...my cam card from comp cams says .026 on both valves....how tight do you guys like the feeler gauge to move when adjusting??? :?:

curtisreed
07-25-2008, 05:57 AM
my cam card from comp cams says .026 on both valves....how tight do you guys like the feeler gauge to move when adjusting??? :?:

If you want them set at .026 use a .025 and .027 feeler guage, just set them where the .025 will go and the .026 won't. Simple as that. Go-Nogo.

Curtis

Tod74
07-25-2008, 07:44 AM
i set mine> exhaust starts to open adjust intake on that cylinder>>>intake starts to open then to full lift then almost closed adjust exhaust...i warm motor to 160 degrees do 1 side then put valve cover back on then warm to 160 degrees then do the other side...i pull the plugs on the side i am doing so the motor turns easy with long rachet on the crank bolt...my cam card from comp cams says .026 on both valves....how tight do you guys like the feeler gauge to move when adjusting??? :?:

I do the EOIC thing too....except I do it with it running. :P

sg1586
07-25-2008, 08:42 AM
How much "speedy dry" do you use per valve adjustment :shock: :shock:

curtisreed
07-25-2008, 08:57 AM
Tod, I think we need a video of that haven't had a good laugh lately.

Curtis

Scooterz
07-25-2008, 04:14 PM
Good job Tod... a little Speedy dry while she is runnin'... with a digital feeler guage, & BAMM! that how she is dunn. I think I will need the video too. Hey- have I mentioned that I think Obama sucks lately??? My DOG is a better candidate... in case you wanted to know.

Tod74
07-25-2008, 04:29 PM
Tod, I think we need a video of that haven't had a good laugh lately.

Curtis

You have to be quick...lol

friends call me "LASH GORDON"

suicidebomb
07-25-2008, 05:05 PM
Tod, I think we need a video of that haven't had a good laugh lately.

Curtis

You have to be quick...lol

friends call me "LASH GORDON"
I love it! :lol: :lol: :lol:

olds48
07-26-2008, 03:17 PM
:lol: :lol: Lash Gordon :lol: :lol: Good one,Todd!!!