View Single Post
Old 03-30-2012, 07:45 PM   #10 (permalink)
serialk11r
Master EcoModder
 
Join Date: Jan 2012
Location: United States
Posts: 1,607

spyder2 - '00 Toyota MR2 Spyder
Thanks: 95
Thanked 326 Times in 253 Posts
Ah I see you're talking about a turbo diesel. I'm not too clear on how different a diesel's powerband looks, but if you shift down, it doesn't hurt economy as long as you're operating the engine near peak efficiency right? Shifting down reduces the load requirement anyways.

I guess the turbocharger + diesel combination changes the rules a little since diesels pass a larger volume of air through at low load than gas engines, and would build up boost fairly quickly. I suppose I didn't think of the fact that higher rpm on a diesel means a lot more gas going through the turbine.
  Reply With Quote