Small parts have a big impact on engine performance.
For example, a good set of lifters will deliver consistent valve timing and maximum power with good oil control. To achieve these benefits, however, you need to make sure you follow the proper lifter installation procedure.
The topic is important enough that Summit Racing created an entire video on lifter installation. It covers new lifter prep, common mistakes you should avoid, and diagnosing lifter issues after installation.
Check it out: