Hey guys,
I was telling a buddy of mine about unpluging the waste gate actuator to get more boost and he was concerned about leaning out the engine. Is this something I need to worry about or does the computer compensate with extra fuel? I have a Bank's 6-gun, 4" exhaust, power elbow, Trans-command, K&N filter(soon to be the Kwik filter), Big Head waste gate actuator, and a trans temp guage.

Thanks

 

Not for your set up. What is actually happening is you are getting more cool air forced into the cylinder head causing a more explosive reaction with the diesel fuel, hence causing a more complete and hotter combustion of the existing fuel. Thus causing more HP, and better fuel economy. (theoretically) Yes you are leaning out the mixture but you are well within the explosive limit range and are not damaging the valves or engine. Basically you are causing a better reaction to occur. With gasser you might need to think of this a little more but your diesel is fine.

 

i am going to try to make this as simple as i can. lean and rich "mixture" does not apply to a diesel motor the way it applies to a gas motor.in basic terms, a gas motor increases power by adding more air and thus bringing more fuel along with it. a diesel is the opposite, it adds fuel to increase power and draw more air. so if you are lean, you just have less power.

 

The PCM adds fuel, based on boost. If you create more boost, the engine will add fuel to compensate.

 

wlihntr is correct. A "lean" running diesel is damaged like a lean running gasser - it is just low on power.

 

Air/fuel ratio is right next to irrelevant on a diesel engine. They have no throttle valve and therefore there is no way to control the amount of air entering the engine. You control the engine with the amount of fuel that is injected at each combustion event.
At idle the A/F ratio is pretty close to 100:1, if I remember right. At WOT it's a lot richer due to the additional fuel being injected.

 

ACK!! I just looked at my post - TYPO - it should have read that "A lean running diesel is NOT damaged like a gasser." Remember, there is NO air throttle on a diesel. Air intake is not controlled by the driver. The intake is wide open at idle, and tiny amounts of fuel are injected. When you press on the accelerator, you are increasing the amount of fuel that is injected, and THAT increases the power.

To reiterate, and agree with Kwik and others - you don't worry about air/fuel mixture on a diesel with regards to lean. Too little fuel equals low power.

The ONLY problem is too "rich" a mixture, that is, too much fuel. This can result in high exhaust gas temperatures which can damage the engine and the turbo. Hence, when adding a chip (which increases the amount and changes the timing of fuel injected), you MUST make sure to increase the air coming in and going out, and monitor your EGT with a gauge.

 

we new what you ment

thats a good point, you can think of "high EGT,s" in a diesel the same way you think of detonation/pre-ingnition (overly lean mixture) in a gasser