to do it you have to do it evenly. if you want to try it (i am not responsible for anything you do) pull the spark plugs and valve covers, pull the timing chain cover and ADVANCE both intake cams 6 teeth on the chains that ties them to the exhaust cams. then put a dial indicator on each lifter and turn the motor over with the vvel actuator at max open by hand, and record the travel of each valve. then adjust one valve down and turn motor over again(if it stops don't force it or you'll bend a valve) and record the change. go through and do the other 23 the same amount (might have to play with it until they are all even) and turn the motor over again. reset the intake cams and turn it over again, if it doesn't hit and all the valves are equal, reassemble and fire the bitch up.
When the motor shuts off it locks the timing gears at full retard the 6 teeth of advancement is the entire range from retard to full advance on the intake valves (plus a 1/2 tooth for saftey). if you want to get really technical you should leave .05 between the valve and the piston so you would have to adjust it close, pull the heads put modeling clay on the pistons put the heads back on, turn it over, pull heads, measure the thicknes of the clay readjust all the valves back a little to get .05, repeat one more time for safety, then reassemble the motor. ITs no small task but theres a guide if you want to try it, again i'm not responsible(unless you get mad power then it's all me
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