Wow.. That underside looks fantastic! I can't see a lick of rust on the frame rails or floor bottom..
I see that the bus has the lowest rated T444e. Mine has the same engine, but is a smaller bus. It does the job well for my size of bus, but for a bigger bus you might want to increase the power output. It ain't hard since a lot can be done simply with tricking the ECM.
Does anyone know if there are any real mechanical differences between the 175hp, 195hp, or 210hp versions of the engine, or is it all programming? That would be my guess. The engine compartments all look the same from what I can see.
Small anecdote: I had the fuel tank off of the bus to paint it and make new mounts. Before we left for our big trip this February I replaced the fuel lines (which - stock from the factory - were actually j844 air brake line and are wonderful to work with). Needless to say, there was a good bit of air in the system after it was all back together. I poured some diesel in the fuel bowl to get us going and it started like a champ.
It wasn't until about 20 minutes of driving later when we had hit the highway that the fun began! We were at cruising speed when I could hear the bus sputter a bit. I figured it was the air in the lines (hoped and prayed it was, that is). After sputtering for a while the bus all of a sudden took off like a bat outta hell! This was at highway speed and I could still feel the acceleration! My guess is that, with all of the air going through the system, the computer was holding the injectors open longer than normal. Once fuel actual hit the injectors it took a while for the computer to throttle them back again.
Anyhow, it gave me a sense of what the engine is capable of.. in short bursts, at least. With a good EGT sensor I'm sure the engine could provide a good bit more power than 175hp with just a simple tuner or resistor mod. My engine has 300000km+ on the odometer, so I'll probably stick with stock tuning.