...the post the other day regarding the taper bored TB with stock plate got me thinking..... I'm replacing the 52mm TB on my 2200 with a 56mm 2.3 TB, just waiting for a cable bracket to arrive. Look at how the intake clamps to the outside of the TB creating a step that can disrupt the air flow. I started by rounding the inner edge and blending it into the throat. I then blended the machined step where the TB tapers to the machined area for the throttle plate. The inside of the throat was fully blended and smoothed, without touching the area around the plate, and satin polished. I'm sure this simple mod will increase airflow, theoretically producing a little more power and maybe better throttle response without losing the bottom end power that a larger TB would.