Turns out the CT4-V Blackwings use a more sophisticated algorithm for detecting catalyst inefficiency, so we were forced to use even higher quality catalytic converters than we had included in our original design. Unfortunately, we had no choice but to increase the price on the catted pipes. This specification change also caused a few more weeks of delay. However, we should be shipping next week, and are accepting the loss and honoring the previously quoted price for customers who had already placed pre-orders.