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Bob, Auto Tech
Category: Chevy
Satisfied Customers: 4087
Experience:  Plus 40 years GM, over 30 certified with Chevrolet, ASE certified Master Tech. (Expired, Retired)
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best way to adjust valves on 350 chevy with roller rocker

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Submitted: 9 years ago.
Category: Chevy
Expert:  Bob replied 9 years ago.
  1. Adjust the valves on V8 and V6 engines as follows:
    1. Crank the engine until the mark on the damper aligns with the TDC or 0 degree mark on the timing tab and the engine is in the No. 1 firing position. This can be determined by placing the fingers on the No. 1 cylinder valves as the marks align. If the valves do not move, it is in the No. 1 firing position. If the valves move, it is in the No. 6 firing position (no. 4 on V6) and the crankcase should be rotated one more revolution to the No. 1 firing position.
    2. With the engine in the No. 1 firing position, the following valves can be adjusted:
    • V8: Exhaust 1, 3, 4, 8
    • V8: Intake 1, 2, 5, 7
    • V6: Exhaust 1, 5, 6
    • V6: Intake 1, 2, 3
    1. Back out the adjusting nut until lash is felt at the pushrod, then turn the adjusting nut in until all lash is removed. This can be determined by checking pushrod end-play while turning the adjusting nut. When all play has been removed, turn the adjusting nut in:
    • 1/2-11/4 additional turn (flat lifter)
    • 3/4-11/4 additional turn (roller lifter V8)
    • 3/4 additional turn (roller lifter V6)
    1. Crank the engine 1 full revolution until the marks are again in alignment. This is the No. 6 firing position (no. 4 on V6). The following valves can now be adjusted:
    • V8: Exhaust 2, 5, 6, 7
    • V8: Intake 3, 4, 6, 8
    • V6: Exhaust 2, 3, 4
    • V6: Intake 4, 5, 6
  1. Reinstall the rocker arm covers using new gaskets or sealer.
  2. If applicable, install the distributor cap and wire assembly.
  3. Adjust the idle speed.
Bob and 5 other Chevy Specialists are ready to help you
Customer: replied 9 years ago.
thanks this engine has holley carb& intake dartheads wild cam also bored&stroked& balanced      what should timing be
Expert:  Bob replied 9 years ago.
Sounds to me like your best bet would be to power time it. I would start at maybe 4 to 6 degrees with no vacuum advance and then let it warm up good and start advancing it just until you get a border line ping out of it when accelerating hard.. Then back it up about 2 degrees, this should give you optimum performance. Only thing to be careful of is that it still cranks ok when hot. If not you will need to retard it a little more. But that is the best way to get maximum efficiency out of it. Thanks
Customer: replied 9 years ago.
thanks bob this is my second visit got you both times great advice your my hero
Expert:  Bob replied 9 years ago.
Well, that was my good fortune. Happy to help and glad you use us. Thanks for the accept and for using JA. Good luck with the project.