Hey guys, I have a quick question. Nearly every Diesel engine made for commercial trucks ( 3/4 ton and 1 ton trucks) have Forced Induction. The only 3 I can think of that don't are the 6.9L/7.3L IDI and the 6.2L Detroit diesel in the CUCVs and Hummers. Why is it that forced induction is so needed on diesels compared to gas engines? I've been in one gas car that had a turbo and that was an F150 EcoBoost.

Is forced induction just way more effective on Diesel engines?

 

Yes it is.

Diesels can run lean, and forcing in more air with forced induction can cause lean conditions. That's a problem in gas engines, but just makes for cleaner combustion in a diesel.

 

So is it also an EPA emissions helper because it makes for cleaner combustion?

 

It allows more power to be made under the strict NOx and particulate limits the EPA has set.
Diesels make power by adding fuel. After about 10-11:1 a/f ratio, you get smoke rather than more power. More air means more fuel which means more power. Diesels are also built heavier to begin with, so they can take boost without any issues within reason.

 

Yes it is.

 

turbochargers on diesel engines is a rather new invention. before the 60's or so, most 4 stroke diesel engines were naturally aspirated.

 

I wouldn't call that rather new

 

well, diesels were natural aspirated longer than they have been turbocharged.
so i consider that rather new.
































but then again, i remember riding my pet brontosaurus to school.

 

The first turbocharged Diesel truck was produced by Schweizer Maschinenfabrik Saurer (Swiss Machine Works Saurer) in 1938.[