SBF Valve Adjustment

Setting valve lash or preload depending on the type of camshaft your running is actually very easy to do. Some will hear abought others doing valve adjustment on there engines and will deviate from trying to do there valve adjusting duties themselves from the lack of confidence or simply telling themselves " i'm not a mechanic". Here is an easy way.

First:

The best sequence to use when setting valve lash is to go by the firing order. Do all of the intake valves one cylinder at a time, then do all of the exhaust valves again one cylinder at a time.

For Hydraulic Lifter Camshafts:

When the exhaust valve just begins to open on the first cylinder in the firing order, adjust the intake valve by loosening the adjusting nut slightly while spinning the pushrod until you feel lash in the rocker arm. Tighten the adjusting nut until the slack is taken out of the rocker arm and pushrod. Lightly turn the pushrod with your fingers as you tighten the adjusting nut, and you should feel a point where there is a little resistance (this is called Zero Lash). Turn the adjusting nut ½-turn past this point, giving you optimal pre-load for the rocker arm, pushrod and lifter. I you want to mesure the amout of preload,look for .030-.060 of preload in a typical hydraulic Lifter. Follow this procedure by carefully adjusting each intake valve according to cylinder firing order.

When all of the intake valves have been set to the proper valve lash, you can adjust the exhaust valves. Utilizing the same procedure as with the intake valves, you need to turn the engine over until the intake pushrod moves all the way up and rotates just past maximum lift. Now the exhaust valve can be adjusted. When all of the intake and exhaust valves have been set with the proper lash, it is common for all the top engine builders to perform a double check by rotating the engine and checking each valve again, starting from the first cylinder in the firing order.

sbf valve adjustment

Solid Lifter Camshafts:

Solid lifter or mechanical camshaft valve lashing is set very similar to hydraulic lifter camshafts. Once again, the most important part is to remember to adjust just one valve on one cylinder at a time – starting with the first cylinder in the firing order and working your way through to the last cylinder.

The only difference in setting the lash on solid lifter camshafts is once you achieve zero lash, you adjust the intake valve by loosening the adjusting nut until you feel some lash on the rocker arm. Then you can set the lash on the valves by the specs listed in your camshaft spec card that came with the camshaft. Spin the intake rocker nut down with the correct thickness feeler gauge inserted between the valve stem and the tip of the rocker arm. Tighten the adjusting nut until there’s a slight drag when moving the feeler gauge. Do not over-tighten or you will risk damage to the camshaft in a short period of time.

 

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