another issue is that diesels just aren't politically correct. i don't care if you can produce reams of paper stating that they are better than gas in every way, there is a large segment of the population in this country that will not, in their lifetime, believe that diesels are good for the planet.
Yes, big issue is public acceptance, despite all facts. It had to do with Oldsmobile 88 and Chevy 6.2, both with a low compression gas engine crank and rods, just because of 70's oil crisis policy, giving it a false start. We in Europe had diesel cars from Peugeot and Mercedes, mostly developed to be a taxi engine, which were 1,000,000km engines.... like a big rig. Just not fast, they were craving for turbo breath in the late 50's because old IDI engines had too much injection retardation at high speeds, so they couldnt get the power by rev'ing it high...
lastly, you assume that the buying public would accept a 200hp diesel. in my world vehicles aren't sold, they are marketed.
Yes, who was that Nascar driver that said "Torque wins races on sunday, but horspower sells cars on Monday" ?? About two months ago there was a BMW with a loud pipe next to me at the traffic lights. I left him with my 140hp 2.5TDI in a big fat smokecloud (EGR valve sticks when i drive too slow for too long) because mine has a wider powerband, it redlines at 4500 but at 4000rpm it starts to drop power... But the 300Nm at 1900rpm is just sweet...
Look at the posts from Renze; in Europe, he is talking small motors with 150HP, that get good mileage. Would never fly here in the States. Works well over there though.
150hp motors arent fuel efficient in 3 ton vehicles... manufacturers reduce the gearing to make them able to come along with the rest of traffic, which makes them high revving engines. You need to reduce RPM to reduce engine friction, and giving it more time for each cylinder to take a deep breath (thats what older atmospheric engines got their max torque from: at that RPM the cylinder fill rate was best, even though fuel injection rate was linear with the rpm)
In a half ton pickup truck, the 150hp 2.5 liter with the 4.11 gears it would require, just wouldnt cut it. In a Ranger it would be a fine engine if it had the torque to pull tall gears.
In general, most people do not "need" 390 or 500hp. They "want" it...
My '01 Dodge is stock except BHAF and 4" exhaust. It was only specced at 235hp. It pulls my 7000lb 5th wheel just fine.
The Cummins 6.7 is now putting out 360hp ?? Then its 4.5 four banger sibling would do 240hp, with driveability at normal driving (from low end torque) comparable to a 350hp gasser. It just wouldnt win a drag race, but thats not what a truck is for anyways....
Mercedes sells 5.1 liter four bangers in their 7.5 to 12 ton distribution truck range, with up to 230hp... That is heavy duty, so max 2200rpm and not 3200 or 3500 like Cummins/Ram...
