Building Your Own Motor
Rocker Arms
Stock Rocker Arms are fine for a Stock Motor, but if you plan on a Performance Camshaft, or stronger Valve Springs, you may want to look into upgrading your Rocker Arms. Roller Rocker Arms are the way to go. Make sure you get a high quality Rocker Arm, Remember your Motor is no stronger than it’s weakest part. You can get Roller Tip Rocker Arms, but for a little more you can get a full Roller Rocker Arm. Rocker Arms come in different Ratios. The Ratios are 1.5,1.52, 1.6, 1.7, 1.72, and 1.73, you will want to check and see what you need for you Motor. The Camshaft Manufacturer will usually have a specific Ratio that you need to use. There are also different Stud Diameters some are 3/8” while others a 7/16”. Some Rocker Arms are on a Shaft. Some Rocker Arms are adjustable, while others are not. This is where the Adjustable Pushrods come in handy.
Adjusting Lifters / Rocker Arms
It is best to adjusting Solid Lifters with the Valve covers off and the Motor not running. Turn the Motor over by hand watching the Rocker Arms on the first Cylinder you are doing. When one of the Rocker Arms has pushed a Valve to it’s furthest extent down into the Cylinder you are working on, then you can check the other Rocker Arm to Valve Clearance using a Feeler Gauge. Back off the Adjusting Nut until the gauge slides between the Valve Stem and the Rocker Arm Tip. There should be just a slight bit of pressure there. If not tighten the Nut until you have the little bit of pressure. You should be able to move the Feeler Gauge in and out of the area. Now, turn the Motor over by hand until the Rocker Arm you just worked, has pushed that Valve the furthest possible into the Cylinder. Now check the other Valve Clearance, like you did the first one. When done with that Cylinder go to the next one, and do the same thing until you have done them all. Make sure you look at the Camshaft Manufacturers Recommended clearances and go by them. Sometimes the Exhaust Valve will be a different Clearance than the Intake Valve. You may have a Cold Tolerance and a Hot Tolerance.
Adjusting Hydraulic Lifters is similar except you have to have the Motor running. This can be an Oily mess. Back the Adjusting nut off until the Rocker Arm starts to tick Loudly and then tighten it back down slowly. Go until the Rocker Arm just stop ticking, this is close to Zero Tolerance. Then for a stock Motor Tighten it down ¾ of a turn further, for a Race Motor you can start out at ¼ turn and go from there. You will get more Torque with the ¾ turn compared to the ¼ turn. Do not go more than one full turn Tighter than Zero Tolerance. And no less than 1/8 of a turn for Top-end Performance. All the Rocker Arms should be adjusted exactly the same.
