Buses are built to order, so the customer chooses from a list of available features. The aforementioned 454 big block had been discontinued by the 2011 model year, and 2000 was the last MY that engine was available in the Chevrolet Express (which would be the chassis used for a school bus). If it has a gas engine, it most likely has the 6.0. The 4.3 V6, 4.8 V8, and 5.3 V8 are other possibilities, in accordance with what the original customer specified. If it's a diesel, it'll have the 6.6 Duramax.
Depends on the model...
129 mph depending on the engine size
No
ford, chevy, or dodge?
Engine size
350
The 2011 BMW Z4 has a 3.0 L base engine size.
The 2011 Ford Flex has a 3.5 L base engine size.
The 2011 Toyota 4Runner has a 4.0 L base engine size.
The 2011 Audi S4 has a 3.0 L base engine size.
The 2011 Toyota Yaris has a 1.5 L base engine size.
The 2011 Audi S6 has a 5.2 L base engine size.