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

Sox 04-06-2008 02:31 PM

Valve adjustment Help
 
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

valve adjments
 
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


Originally Posted by olds48
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


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?

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


Originally Posted by suicidebomb
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)


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