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-   -   Valve adjustment Help (https://www.racingjunk.com/forums/showthread.php?t=20465)

fishman1 04-08-2008 03:42 PM


Originally Posted by sg1586
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

settings
 
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


Originally Posted by sg1586
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


Originally Posted by Tod74

Originally Posted by fishman1
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

Setting valves
 
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


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