Cummins 8.3 Allison MT643 Performance What to expect???

[TomC]

8.3 is currently available up to 350hp and 1,000lb/ft torque.  The 8.9 liter ISL is the same block and available up to 450hp and 1300lb/ft torque for RV use-this would be my choice, and will be the engine I use IF I need to swap out my big Caterpillar 3406B because of smog laws.  Good Luck, TomC

[mikelutestanski]

Hello:   I average 7.4 with a mechanical 1989 L10 @300hp  with a B400R and 4.625 rear end.  THe double OD gears really help.   The roadranger behind an L10 will get another mile or so in my opinion.
   The computer engines do better mileage wise but can be more of a headache when they go south.  Not that they do that often and parts are hard on the wallet however the guy that is getting 10 or so has a sweet setup albeit driving habits do make or break mileage.   
    Any way good luck with your conversion/swap.  it can be challenging but a very worthwhile exercise especially when its running again..
   FWIW 
   Regards and happy bussin   mike

[TomC]

The mechanical L10 is a great engine for a bus.  It is compact enough yet robust for years of service.  And while it won't get the fuel mileage of an electronic engine, all you need is one electronic failure and all the fuel savings plus more go away.  Good Luck, TomC

[luvrbus]

I would go for a 3306DI Cat engine before the L10 Cummins far better engine been around since the 60's.DI stands for direct injection early 3306 engines had a pre combustion chamber.
good luck

[NeoplanAN440]

I agree,the L10 is a nice engine!!

we just did the testdrive in the donor truck and im very happy with it.its hard to compare a empty tractor with my loaded bus,but it feels good so far.

now i have to decide if we take it one step up and even use the 9 speed manual or search for a ht 740 or b500??
i think it costs more to change the ecu settings on my ht748 to lower rpm and shiftpoints,then changing transmssions.
i have to admit,that i have a interested buyer in my engine tranny combo,and he wants the whole setup to make his swap easier!!! this would help me with the hidden costs that will show up while installing the new drivetrain.
also the transmission choice will give us the factor what rear end ratio we will use.

still lots of questions!

[TomC]

I think you'll find that trying to add a manual shifter and a clutch pedal with linkage will be way too much work.  I wouldn't worry about changing the shift points on your HT748, since both the 8V-71 and L10 both operate up to 2100rpm.  Just make sure your linkage is adjusted correctly to take advantage of partial throttle shifts.  I know on my V730 on light acceleration, I can see early shifts where the engine rpm can come down to 1100rpm after the shift.  Good Luck, TomC

[Zeroclearance]

Dan Holter has a complete Detroit S50 and B500..   Sell your powerplant and drop in a S50 and B500 that came from a transit coach.