Author Topic: valve adj  (Read 3197 times)

68Zproject

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valve adj
« on: June 07, 2014, 09:05:32 PM »
Just got most of my engine put back together and before I put the intake on I want to adjust valves.  I don't have the 30-30, I have a Comp xs282s.  When I degree'd the cam I noticed that the lifter stayed at 0 lift for quite a while.  Can I adjust the valve clearance at any point on this 0 lift?  Also clearance is listed as .016.  I assume this is hot.  If it is, what do I set it to for now?
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janobyte

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Re: valve adj
« Reply #1 on: June 07, 2014, 09:39:41 PM »
TDC and run through the valve order like any other solid cam ( #1 E I should be closed and sloppy rocker arms ) Quick search will give you the order, than rotate 180 degrees. I've used Mac Quick sticks for years ( Google them)

Set at .016 ( manufactures recommendation I'm assuming) little drag on the feeler gauge, that will get you fired up for break in, check again after the cam broken in ( follow procedure ,important) you will be fine.

The procedure listed in here for the 30-30 is great, same one we use on the race motor running a hydo roller,yep,  it's profile requires a little slop in the valve train per the engine builder.


Your running nothing radical, modern profile, traditional procedure.

68Zproject

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Re: valve adj
« Reply #2 on: June 07, 2014, 10:26:45 PM »
I get nothing on the mac stick except all sorts of Apple stuff.  The cam was already broken in, I had a few thousand on the engine when I had to do the tear-down.  I found this one.  I assume that will work?

http://www.camaros.org/forum/index.php?topic=4268.0
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cook_dw

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Re: valve adj
« Reply #3 on: June 07, 2014, 10:42:49 PM »
I have always used the EOIC.

Exhaust valve begins to Open adjust the intake.

Intake valve begins to Close adjust the exhaust.

Yes the 0.016" is hot..  Add 0.002" for thermal expansion.


Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28

cook_dw

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Re: valve adj
« Reply #4 on: June 07, 2014, 10:49:17 PM »
Sorry I started my post a hour ago and got side tracked.  Your thread you posted is basically the same as my post.
Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28

68Zproject

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Re: valve adj
« Reply #5 on: June 07, 2014, 11:05:07 PM »
So .018?
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janobyte

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Re: valve adj
« Reply #6 on: June 07, 2014, 11:36:55 PM »
yea,listen to Cook.

 The Quick Sticks laid down on the heads with cut outs for the push rods and referenced each cylinder with both valves closed. I tried looking them up, may not make them anymore. >:(

cook_dw

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Re: valve adj
« Reply #7 on: June 07, 2014, 11:44:54 PM »
So .018?

Yes. That way when it is hot it'll be 0.016"
Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28

ko-lek-tor

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Re: valve adj
« Reply #8 on: June 08, 2014, 12:33:20 AM »
I am sure there will be someone who does not approve of how I do valves, but here goes: First, a four stroke engine makes 2 complete revolutions of the crank or 2 x 360 degrees = 720. Divide by the # of cylinders (8 in this case)  = 90 and that tells you every 90 degrees is top center on a compression stroke (both valves closed) for a cylinder. Mark your balancer every 90 degeres (4 marks counting TDC). Start with TDC on #1 cylinder, adjust clearance for both valves. Crank engine clockwise (looking from front of car) with socket to next mark (90 deg)(easier if plugs are out) do next cyl. in firing order  (8 in this case). and so forth till all 8 are done. 18436572 is firing order with odd #s on LH, drivers side bank, even on RH. This ain't brain surgery and exact TDC for each cylinder is not critical (I just like to be exact when I do it), but you can use a remote starter and bump it around if you have a good R. Starter that can let you do small bumps. If you miss one, just do the next one in order and come back to the one you missed on the next revolution x 2. When you are at TDC for ea. cyl. after setting lash each rocker will have a little, but not excessive play which will be the lash setting of course. But just grab each rocker and double check and by feel , you'll know it is pretty much right.
« Last Edit: June 08, 2014, 01:45:47 AM by ko-lek-tor »
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ban617

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Re: valve adj
« Reply #9 on: June 09, 2014, 09:21:05 AM »
 .016 is that a hyd cam ? I would say .02 tighter cause when it warms up the lash will get looser.

cook_dw

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Re: valve adj
« Reply #10 on: June 09, 2014, 12:00:58 PM »
Solid lifter.


I would say .02 tighter cause when it warms up the lash will get looser.

What happens to steel when it is heated?

It expands.  Which will close the gap.  So if the cam card calls for 0.016" hot then you add 0.002" to that number for a cold setting.  Set the lash to 0.018".......


Aluminum heads are a different story.  You would subtract 0.006" on the hot lash spec.  If its an aluminum block & heads you would subtract 0.012"
Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28

68Zproject

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Re: valve adj
« Reply #11 on: June 09, 2014, 05:32:19 PM »
Thanks guys, got em all to .018.  When  I get it running, I'm going to let it go for 20 min or so and then do them again hot and I should be set for a while.
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cook_dw

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Re: valve adj
« Reply #12 on: June 09, 2014, 07:42:49 PM »
I always do the break-in and then upon shut off adjust the valves again and drain the oil.  That is a pretty good little cam you used.  What is your complete setup?  Do you plan to put it on a dyno?
Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28

janobyte

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Re: valve adj
« Reply #13 on: June 09, 2014, 11:59:36 PM »
I read the specs, agree. DWC usually beats me to the punch.

cook_dw

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Re: valve adj
« Reply #14 on: June 10, 2014, 12:41:03 AM »
:)
Darrell Cook
1967 LeMans Blue SS/RS L35 clone
1968 Rallye Green SS L78 - unrestored original
1968 Matador Red Z28