Can I get an explanation on what Under drive harmonic balancer and Manifold insulators do?

Underdrive harmonic balancer The way an under drive balancer/pulley increases power is that it reduces the amount of power going from the engine to drive engine accessories such as alternator, water pump, power steering pump etc. It also reduces the mass moment of inertia of the balancer meaning that it takes less power to accelerate . Manifold insulators Manifold insulators work by reducing heat transfer (via conduction) from the hot cylinder heads to the inlet manifold. This improves power and power consistency as the inlet manifold remains consistently cooler There installation also increases intake runner length, improving intake manifold scavenging characteristics, which means more power in the useable engine RPM range