??? How come that both the locomotive pair and Cafe power car inform us (both on-line and in the catalogues) that "Modelers can now accurately duplicate Amtrak's standard eight-car Acela® consist by adding to the Spectrum® Acela® Express train set, or by building their train one car at a time." whereas catalogue numbers 89972, 89973 & 89974 do not appear anywhere I can see? ???
That is a good question, I have only seen the Business End car availble at online retailers, but it is very far and few between :( I would like to make my Acela have the 8 cars as well.
Just be prepared for the possibility that the powered cafe car might not have enough power to move all eight cars reliably. Mine can't, except on straight, level track. On the flip side, I've heard from others who have full sets that can negotiate curved grades with no problem. It's like some of Bachmann's other products, the QC can be very inconsistent.