Quote:
Originally Posted by christofoo
This thread didn't die, and I'm still getting foam flecked PM's from t vago, so I want to try delving back into whether or not DCD will improve FE.
|
Quote:
|
Originally Posted by t vago
Quote:
|
Originally Posted by christofoo
PS, are you saying that you design ICE's for a living? Otherwise don't give me that. Actually, one way or the other, be nice.
|
Your latest foray into that charlatan's thread illustrates my point rather well. How many edits and "oops" did you do there? Learn more about what you're trying to comment on. |
Apparently, in your universe, this counts as "foam-flecked." Alright, prima donna, let's have at it.
Quote:
Originally Posted by christofoo
But I want to try simplifying my argument again, largely for previously mentioned reasons.
So, here goes:
==============================
DCD vs lean-burn: Why does lean-burn work and DCD not?
Suppose the lean-burn engine is operating at 25% (er, how to say this?) leanness, by which I mean stoichiometric AFR X 1.25.
Compare to DCD with 25% of cylinders deactivated, 75% at stoichiometric AFR. All else being equal, including valve timing.
If you think I'm wrong, explain to me: - Is there a difference in air mass flow rate?
- Is there a difference in manifold vacuum?
- Whatever else you think requires consideration.
|
Lean Burn works because intake manifold is lowered, compared to an engine running at stoichiometric. DCD does not work, compared to Lean Burn, because you're placing a drag on the engine (in the form of non-firing cylinders that are still pumping air - therefore consuming more fuel than necessary).
Figure the rest of it out on your own, professor.