Sbc timing & valve adjustment (Tuesday) question

M92PV4U

M92PV4U

Falling Down
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May 19, 2020
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D.p. Ca.
According to the "book"
You adjust With #1 @ TDC
Exhaust 1 3 4 8
Intake 1 2 5 7

You adjust With #6 @ TDC
Exhaust 2 5 7 6
Intake 3 4 6 8

But when I'm on #1 tdc #8 Exhaust valve is open. This doesn't seem correct to me and think that I have something assembled wrong?
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I'll just turn the crank until the the lifters are off of the lobe and adjust them that way, but I CAN'T SEE what I'm doing wrong and I'm hung up on that :homer:
 
Not an expert here, but I'd assume that spec assumes the engine has a stock cam which likely has shorter duration.

If you have a cam with longer duration, it could explain why you're seeing the exhaust valve still open with #1 at tdc.


This is coming from someone who adjusts sbc valves with the engine running, back off the rocker but til it just starts clacking, then tighten it back (I think I did a half a turn) so YMMV.
 
If I remember both dots need to be on top for #1 tdc for #1 timed to fire.

Dad always set the timing to line the dots up with the cam at 6 o clock and the crank at 12 and always ended up having the distributor 180 out.
 
Yes, if you want it on TDC Compression #1. Both lifters for cyl #1 should be on the base circle now.

You installed it correctly. No problem there.
 
YJ4Rox said:
this for sure. If you drop the distributor in now its 180 out.
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I do the spin the push rods and tighten until snug, rotate crank 90 degrees, repeat, rotate 90 repeat, etc.. thats on hydraulic lifters. then tighten 1/2 to 3/4 turn.
 
First back them all off and rotate the engine a few revolutions, if it rolls over freely with no binding you're probably okay as far as assembly.

Then just do them cylinder by cylinder.
 
I've always done it with it running. Didn't know that's not "correct"
 
The easiest way the is Exhaust Open Intake Closed method.

Start at the front on which ever bank you want. On a SBC this would be an exhaust valve. Rotate the engine over until the intake valve on that cylinder is almost closed. Adjust the exhaust valve. Then rotate the engine until the exhaust valve just starts to open. Adjust the intake valve. Move to the next cylinder in line. Repeat.
 
You guys are making this way to ****ing hard. :lmao:

Dont matter where its at , back them all off loose. Then just start setting them at 0 lash/preload. Rotate a quarter turn, then whatever ones are loose, set at zero lash/preload. Repeat this 8 times.

Now you have ALL of them at zero preload. Then go and give them all 1/2 , 3/4 or whatever your preload is.

Now you are done.
 
Alexis700 said:
You guys are making this way to ****ing hard. :lmao:

Dont matter where its at , back them all off loose. Then just start setting them at 0 lash/preload. Rotate a quarter turn, then whatever ones are loose, set at zero lash/preload. Repeat this 8 times.

Now you have ALL of them at zero preload. Then go and give them all 1/2 , 3/4 or whatever your preload is.

Now you are done.
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Going in firing order makes it less likely I'll skip some


I still do, but it's easier to notice :laughing:
 
When I do the lash on a cummins I do EO IC method, but thats solid flat tappet camshaft. Also easier to keep track of where you are at on a inline 6.

On the small block or any gas v8, I have found the Vice Grip method to work awsome.
 
Some of you would have a brain aneurysm trying to run the overhead on a series 60 Detroit and the mental image of a group of grown men crying next to a semi truck is doing wonders for my mental health.


Cheers boy's :beer:
 
I've always just started at one TDC, adjusted all the ones that weren't open, then roll the crank around once and do all the other ones.
 
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