saying the fuel economy wont improve. it would for sure, especially if you keep the very high rear end ratio. and you probably could convert it to stick as well. if converted to a stick you would need to change the rear ratio to the 369 of the 240. your estimate of the weight difference for the motors is i think way off. i bet the 240 only weighs about 125# less. but if you converted to stick it would save another 40 or 50.

the performance would be very poor, worse than a 240, though not as much worse as you might imagine. if you put in a 240 rear end in, in the end you will find that the sd body wouldnt be all that much heavier than a 240 and it is slicker and i think not any bigger in frontal area. it might beat a 240 in highway fuel mileage. the extra weight will always affect the acceleration. but a 240sd would be about the same weight as a 240 with one large passanger, i bet.

still, i wouldnt do it myself and wouldnt recommend it. i would just get a nice 240 and enjoy the simplicity of its less elaborate design. and a good 240 retains its value excellently. a 240sd would be difficult to sell, i think.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.