Lee Levitt wrote: > > Any thoughts on peak efficiency for the 2.5 turbo?
It looks like all the turbos (before the 3.5 anyway) were rated for peak torque at 2400rpm, so that's probably a good place to start. The timing advance graph I saw was probably on the W126 CD for the 1986 OM603, it showed the injection reaching full advance by 2000-2300rpm. There's a guy on mercedesshop who put a 190E 5sp tranny in his 190D 2.5t, I figure he's doing 80mph at 2400rpm. He got 39mpg on a long trip, I wonder if he could have done better with a bit less overdrive. I figure I'll be getting around 62mph at 2400 in my 190Dt with a non-overdrive 5sp, which should give me great mpg (I'm hoping 45mpg) on two lane roads, but not quite as good at 75mph on the freeway.
