The euro 280 motor has a lot of torque and power. I put a 307 in the rear of a us spec 280 and it still has plenty of power. the increase in mileage never matched what I expected it to though. A 354 is about 16% more than a 354 more or less. I would expect it to increase the mpg about 2 mpg. Still not stellar.

I don't know what you have been getting but my euro 280e with the five speed with overdrive got in the low 20s highway.

it was really nice to drive though. smooth powerful and about the same life expectancy as the bulletproof 616 and 617 na diesels.

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.