#1
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Setting valve lash on a GEN I SBC
I used this first method when doing my motor and it worked flawlessly. I havent had to make a single adjustment.
1) Set the timing mark to 0 TDC #1. How do you know if you are TDC #1? Well rotate the crank slightly in both directions and see if either the intake or exhaust push rod of #1 cylinder moves. If it does you are probably TDC #6. Rotate the crank another 360 degrees and you should be there. 2) Now you can set the following valves: exhaust - #1, #3, #4, #8 intake - #1, #2, #5, #7 To set the proper valve lash you must set the preload of the lifter. First you must take the slack out of the lifter, push rod & rocker arm assembly. Do this by turning the push rod as you tight down the rocker arm nut. As soon as you "FEEL" some resistance in the push rod stop tighten the rocker arm nut. Now turn the rocker arm nut down 1/2 to 3/4's (max 1 full turn) of a turn in 1/4 increments. This sets the preload. 3) Rotate the crank 360 degrees and set the other half of the valves exhaust - #2, #5, #6, #7 intake - #3, #4, #6, #8 Method # 2 Another way to set the valves is to "set EXHAUST when the INTAKE just starts to open then set the INTAKE when the exhaust just starts to open". This method requires you to rotate the crank for EACH cylinder. But it insures that the lifter is on the bottom of the cam lobe. Method # 3 This method is very messy as you have the engine running. You will need clips to cover the oil holes in the rocker arms or use 1/2 of an old valve cover that has been trimmed to allow you access to the rocker adjusting nuts. First you set the valve adjustment so there is some preload on the lifters. Now start the engine. Back off the rocker arm nut until you hear/feel the rocker arm click. Now, adjust the rocker arm nut in 1/4 turn increments to 1/2 to 1 full turn. |
#2
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After the first time I read 'Method 1' I made this diagram so I could keep drinking wiskey and just look for the right color when setting the lash !!!
Makes it easy !!! First get that one and that one, then skip that one and do that one ! Last edited by John in RI; 03-22-2010 at 05:19 PM. Reason: edit |
#3
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if you have a monster cam in it the first method will not work the best way I have found is this
Step Rotate Adjust exhaust Adjust intake Number Crank to spec lash to spec lash ------ ----------- -------------- ------------- 1 Rotate cylinder #1 to TDC 2 --- cylinder #8 cylinder #2 3 90 degrees cylinder #4 cylinder #1 4 180 degrees cylinder #3 cylinder #8 5 270 degrees cylinder #6 cylinder #4 6 0 degrees cylinder #5 cylinder #3 7 90 degrees cylinder #7 cylinder #6 8 180 degrees cylinder #2 cylinder #5 9 270 degrees cylinder #1 cylinder #7 this allows for lead in on solid cams where some times they can still be upwards of .03 thousands in lift at TDC
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Nitrous is like hot girl with STD's. You know you wanna hit it, but your afraid of the consequences |
#4
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dam it i have no clue on how to make that look good dam it
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Nitrous is like hot girl with STD's. You know you wanna hit it, but your afraid of the consequences |
#5
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you can also set lash at the base circle of the cam
twirl pushrod while tightening rocker nut till a slight resistance is felt. then 1/2 turn more and it set. fool proof
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"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my ride." -Amen US NAVY RETIRED |
#6
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Yup thats method #1 in the OP.
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5.3L LSx, Fbody .500 cam, TH400, 4500 Stall, Moser 9" |
#7
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yes but if you have a HUGE solid cam you need to set the valves like i stated if you dont you will still be on the clearance ramps at TDC the other ways work with any hydro cam's and most of the solids below 250 @ .050 duration. hear is a explanation of why. there mane focus is on the older cams but it still holds true for many larger cams
http://65corvette.nonethewiser.net/t...AdjArticle.pdf
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Nitrous is like hot girl with STD's. You know you wanna hit it, but your afraid of the consequences |
#8
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Good shit boomer, good thing my hyd. roller is below 250 @ .050 anyways
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5.3L LSx, Fbody .500 cam, TH400, 4500 Stall, Moser 9" |
#9
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my old solid roller was 258 and 264 it ran way better after i set it like that before it clacked like hell and didnt pull as good
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Nitrous is like hot girl with STD's. You know you wanna hit it, but your afraid of the consequences |
#10
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Nice write up, too complex for me though. I like mine "tighten bolt to XX Ft Lbs"......done
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-Nick 9/11/01 NEVER forget! |
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