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Re: How to adjust valve lash???
[Re: 540challenger]
#275375
04/02/09 08:18 PM
04/02/09 08:18 PM
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Joined: Nov 2004
Posts: 2,119
sc
tjmarcus1
top fuel
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top fuel
Joined: Nov 2004
Posts: 2,119
sc
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Quote:
hey guys i putting together my magnum heded small block right know.
When i set the vavlues i prefer the method were you set the lash by watching the intake and the exhaust closing.
I am i correct as when the intake is just opeing you set the exhaust side.
then when the exhaust valve is closing i set the intake side??
i believe it's when the exh. starts to open you adj. the intake. fyi. i have an engine on the stand now, and just for the sake of it, i set the lash the old fashion way. get the motor on #1 firing pos. and set both valves. from there go thru the firing order. then i checked them using the opening and closing method. i found virtually no diff.
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Re: How to adjust valve lash???
[Re: RodStRace]
#275377
04/02/09 09:14 PM
04/02/09 09:14 PM
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Joined: Feb 2005
Posts: 5,207
Menomonee Falls
DemonDust
master
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master
Joined: Feb 2005
Posts: 5,207
Menomonee Falls
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Starting at #1 cylinder, rotate the engine until the #1 exhaust rocker just starts to open the exhaust valve. Set the valve lash on #1 intake rocker at this time. Continue rotating the assembly and stop when #1 intake rocker starts returning from full lift. The lash on #1 exhaust can now be set. Continue this procedure for the remaining cylinders.
Last edited by R5P7Duster; 04/04/09 09:13 AM.
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Re: How to adjust valve lash???
[Re: camdog440]
#275383
04/02/09 09:54 PM
04/02/09 09:54 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
That doesnt work with big duration cams
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Re: How to adjust valve lash???
[Re: MR_P_BODY]
#275384
04/03/09 12:09 AM
04/03/09 12:09 AM
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Joined: Mar 2003
Posts: 15,491
the boonies
aarcuda
I Live Here
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I Live Here
Joined: Mar 2003
Posts: 15,491
the boonies
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Quote:
Adjust the intake when the exhaust is starting to open
adjust the exhaust when the intake is starting to close
 best way EVER!
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Re: How to adjust valve lash???
[Re: MR_P_BODY]
#275386
04/03/09 06:01 AM
04/03/09 06:01 AM
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Joined: Sep 2008
Posts: 34
Sydney, Australia
B-STUNG
member
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member
Joined: Sep 2008
Posts: 34
Sydney, Australia
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Quote:
Quote:
That doesnt work with big duration cams
This method always works, as it relates to firing order, and not cam size. For example, When #1 is at TDC, #2 intake will *always* be on the base circle if the standard Mopar v8 firing order is used (irrespective of how large or small the cam is) and the relationship applies all the way through.
The key to using this method is to ensure that rotation is fairly close to 90 degrees. In my case I have timing marks every 90 degrees on my balancer which makes it easy knowing how far to rotate, and the tappets are set within 2 full rotations of the engine. 
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Re: How to adjust valve lash???
[Re: B-STUNG]
#275387
04/03/09 06:55 PM
04/03/09 06:55 PM
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Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
MRMOPAR622
top fuel
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top fuel
Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
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I was told by a big Mopar man that on a big block Mopar you need to let the exh. open about half way before setting intake.Is this right? Engine seems to run a little better. He still said to set exh. when intake was almost closed. MetalStrom(hope thats the right name) When I adjust my valves and most other engine work on my dragster I set on I think what is called a shower chair(stool)  .For people who cannot stand up for long in a shower.It really saves your back.
"To Be The Man'You Have Got To Beat The Man"
"T/D and Pro-Bracket Racer"
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Re: How to adjust valve lash???
[Re: MRMOPAR622]
#275388
04/03/09 08:36 PM
04/03/09 08:36 PM
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Joined: Jul 2005
Posts: 8,647
ELYRIA,OH
blownzoom440
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Joined: Jul 2005
Posts: 8,647
ELYRIA,OH
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Quote:
MetalStrom(hope thats the right name) When I adjust my valves and most other engine work on my dragster I set on I think what is called a shower chair(stool) .For people who cannot stand up for long in a shower.It really saves your back.
that chair would make me the reciever of some terrable jokes with the dragster crew.that is a good idea though! 
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Re: How to adjust valve lash???
[Re: B-STUNG]
#275389
04/03/09 09:42 PM
04/03/09 09:42 PM
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Joined: Aug 2005
Posts: 99
Louisville, KY
Allan_G
member
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member
Joined: Aug 2005
Posts: 99
Louisville, KY
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Quote:
Quote:
Quote:
That doesnt work with big duration cams
This method always works, as it relates to firing order, and not cam size....
Sorry, but this method does not always work, because many cams nowadays have very long ramps, which in turn means that the base circle portion of a lobe is very small. If you try to set the lash on one of these cams using that 8-point method shown in the diagram, you will be loose by a few thousandths. Sure, "it will work", but you're giving up valve lift.
-Allan
(FKA Racer Al back in 2000...)
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Re: How to adjust valve lash???
[Re: aarcuda]
#275390
04/03/09 10:23 PM
04/03/09 10:23 PM
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Joined: Nov 2003
Posts: 7,348
Mt.Vernon ,Ohio
VernMotor
master
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master
Joined: Nov 2003
Posts: 7,348
Mt.Vernon ,Ohio
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Quote:
Quote:
Adjust the intake when the exhaust is starting to open
adjust the exhaust when the intake is starting to close
best way EVER!
This is how I do it.. do one side then do the other lots faster
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Re: How to adjust valve lash???
[Re: VernMotor]
#275391
04/03/09 10:36 PM
04/03/09 10:36 PM
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Joined: Jul 2005
Posts: 8,647
ELYRIA,OH
blownzoom440
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Joined: Jul 2005
Posts: 8,647
ELYRIA,OH
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Quote:
Quote:
Quote:
Adjust the intake when the exhaust is starting to open
adjust the exhaust when the intake is starting to close
best way EVER!
This is how I do it.. do one side then do the other lots faster
that works for the Lake Erie Monster crew.
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Re: How to adjust valve lash???
[Re: Allan_G]
#275392
04/04/09 05:30 AM
04/04/09 05:30 AM
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Joined: Sep 2008
Posts: 34
Sydney, Australia
B-STUNG
member
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member
Joined: Sep 2008
Posts: 34
Sydney, Australia
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Quote:
Quote:
Quote:
Quote:
That doesnt work with big duration cams
This method always works, as it relates to firing order, and not cam size....
Sorry, but this method does not always work, because many cams nowadays have very long ramps, which in turn means that the base circle portion of a lobe is very small. If you try to set the lash on one of these cams using that 8-point method shown in the diagram, you will be loose by a few thousandths. Sure, "it will work", but you're giving up valve lift.
-Allan
The 8-point method puts you very close to the center of the base circle (within 20-30 degrees) for the respective tappets to be adjusted.
While the ramps may be long on some cams, clearly they cannot extend that close to the center of the base circle. If they did, you would have a cam with an advertised duration > 600 degrees and you would have next to no compression.
If executed per the chart, the method works (if it does not, there is a serious problem with the engine).
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