Driving with vdc off

[RJS5689]

Do you even know how a diesel throttle works? There is no butterfly valve to control intake of air into the engine. The engine takes in all the air it possibly can every intake stroke, meaning at least 100% volumetric efficiency at all times once you factor in turbo boost. A diesel throttle is attached to the fuel pump on older models, or the fuel regulator on newer models, and regulates the amount of fuel the engine consumes to regulate engine speed. That's why when you slam on the gas pedal in a diesel you get a puff of black smoke, it's soot and unburned fuel because the combustion chamber isn't hot enough for complete combustion yet. Once the chamber warms up it burns all the fuel and the engine will have an easier time accelerating. Until the chamber has warmed up it may seem like it's bogging, because of the rich mixture at the instant you step on the gas. Newer drive by wire trucks hold back the throttle a tiny bit to let the combustion chamber warm up, promoting complete combustion and saving fuel. Once complete combustion is possible, the ECU will open up the throttle the rest of the way. Diesels have a Stoichiometric air fuel ratio that is variable, meaning the engine will run at different air fuel ratios. The IDEAL ratio is 14.6:1, whereas gasoline is 14.7:1. It's not uncommon for a diesel to run with anywhere from 3:1 all the way to 60:1. Since the fuel flow is controlled by throttle position, the air fuel ratio will be constantly variable, thus one could expect different performance from different throttle inputs. You're idea of going fast is slamming the gas pedal all the way to the floor. In a diesel pickup, you want to give it throttle progressively to promote a consistent air fuel ratio. A gas engine alters the amount of air the engine consumes when you give it throttle, then trims the fuel mixture to match. A diesel trims the fuel to alter RPM,s then the engine naturally will suck in more air in an attemt to maintain an ideal Stoichiometric air fuel ratio.

 

And yes, when it comes to diesel trucks, I do know everything. When it comes to ricers, I know enough to define you as one... That comment about how you always win proves it. Even when you don't win your mentality is that you could've won if your clutch didn't slip, or you didn't have so much turbo lag, or something.

 

I'm done.

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WIN! Let's be friends....haha.