With the kind of rod angle that you'd have to run with the 4.0 crank in the 2.8 block the end results would not rev as easily as the stock 4.0. The 4.0 has a longer rod, which has a smaller angle and thus puts less pressure on the thrust side of the cylinder wall.
I have put 400 cu. in. small block Chevy cranks into 350 Chevy block, thus getting a 383 cu. in. engine, but the end result doesn't rev as quickly as the 350 does. R.P.M.s are also limited too. It has a ton of torque, which is its strong suit. It is good for a heavy car that needs a lot of torque to get it going.
It is nice sometimes to sit and dream about all the possibilities, but in actual operation, will act differently to what we dream.
Jose
