New EGR Stacks on Shells

In the ramp-up to the new Volvo 12.7 liter engine on Prevost shells, it seems that the interim step (which can be viewed over at www.prevost-stuff.com) is going to be the DD Series 60 with basically a catalytic converter going up through the roof. The rationale for the roof deal is twofold. First, the temperatures off the rack are at about 1500F, which is pretty hot on asphalt, so a converter with diagonal plates will catch particulate. When the particulate accumulates, there will be fuel injectors within the converter to burn it off. Fuel economy will be affected in the range of 2-5 percent).

All this will require a box up from the engine up top to the roof, taking up some storage/build space inside of the the rear of the bus. Prevost Car has been awfully busy on this project and plans for a 'cut-in' date of March for H3's, and September for the XL-II's. There is yet to be a specific date for complete implementation to the Volvo, but something kinda like 08. Since the old Mack plant is not up and running, it would be too soon to tell, I guess.

The word on the street down here in Prevost alley (Florida) is that if you are in the market for a new bus, get one with the current system in it, time-tried and proven. No word on pricing of the new shells with the upgraded EGR/conversion or Volvo engines yet, but doubt they will go down.

If you see what you want, get it while get getting is good.

Oh, (whew) there will not be a requirement for prior year models to meet the newer EGR and particulate requirements. So whatever you got, you got.