is there much difference 1980 mci and a 1990

[belfert]

Electronics came about well before the four strokes became common in buses.  The DDEC was originally used on the 6V92 and 8V92.  I don't think any 8V71 was DDEC equipped, but don't trust me on that one.  You don't have to have an engine with electronics to have a tranny with electronics.

Personally, I choose to get a bus with four stroke series 60 and B500 tranny to get better mileage and potentially longer engine life.  Also, just about any diesel mechanic can work on a Series 60, although there is labor savings by working on your own engine.

I get 8 to sometimes 9 MPG with my bus.  Later MCI 102s with the 2 stroke and auto tranny can be as low as 5 MPG.  Now, some of the GMCs with manual tranny have been known to get 10 MPG and better, but they are also smaller and lighter buses.