DPFE (EGR) Sensor delete

I'm not the brightest beet in the basket, I know. And I've not kept up on the technologies in engines. I thought EGR was on all gas engines. Is there a simpleton explaination of how they got away from EGR?

cups said:

I'm not the brightest beet in the basket, I know. And I've not kept up on the technologies in engines. I thought EGR was on all gas engines. Is there a simpleton explaination of how they got away from EGR?

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But I do know that the 4th gen LS engines don't have it, either. Some of the 3rd gen LS engines did.

After doing some research, the other way around it is with the amount of overlap in the camshaft design (leaving more exhaust in the combustion chamber).

So there may be some system/controls that will put/leave exhaust in for re-combustion?

The 6.2L has variable valve timing, this is used specifically for exhaust emissions, not performance like the little Honda's cute little v-tec, I'm not sure exactly what it does but I believe it opens the exhaust valve slightly earlier than normal so that exhaust gas can leave the cylinder sooner and allow more time for cylinder cooling between power cycles, the other option is that it closes the exhaust valve sooner than normal to keep some of the exhaust gas in the cylinder and reduce the total combustible volume of the cylinder (exactly what egr does except it keeps exhaust from going into an actuator that can fail or plug up, and from going through the intake tube to get back into the cylinder to prevent exhaust buildup in the intake)

So I'm thinking at this point, ittybitty should check for proper operations of the various control systems. Maybe check for error code or take to Mike at 5-Star. Maybe it's something g a tune could help?

I'm thinking the loss of throttle response he is feeling is just the reduced low end power, he has changed the rpm at which the engine scavenges, which is the flow of the exhaust gas leaving the cylinder pulling more intake air in, there are waves in the exhaust that do not affect total flow of the exhaust, the amount of time the wave takes to go from the exhaust valve down to where it bounces off a restriction in the exhaust pipe and back to the valve determines when scavenging occurs, with the stock muffler system this is designed to occur at low rpms to increase driveability, when you change the system it can occur at a higher rpm, and with most aftermarket systems it occurs at much higher rpms than stock, correct me if I'm wrong about what I think you're feeling ittybitty

Cleave said:

I'm thinking the loss of throttle response he is feeling is just the reduced low end power, he has changed the rpm at which the engine scavenges, which is the flow of the exhaust gas leaving the cylinder pulling more intake air in, there are waves in the exhaust that do not affect total flow of the exhaust, the amount of time the wave takes to go from the exhaust valve down to where it bounces off a restriction in the exhaust pipe and back to the valve determines when scavenging occurs, with the stock muffler system this is designed to occur at low rpms to increase driveability, when you change the system it can occur at a higher rpm, and with most aftermarket systems it occurs at much higher rpms than stock, correct me if I'm wrong about what I think you're feeling ittybitty

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The scavenging effect was a common issue with certain exhaust systems on my Titan forum back in the day. For example, the Banks Exhaust for the Titan used a 3.5" downpipe and 3.5" exhaust through a barely restrictive muffler and then out of a 5" tip. This large diameter downpipe caused the lack of scavenging and caused a loss of low end torque, but did cause overall higher HP numbers. The fix was to get a 3" diameter downpipe (most used Volant) to attach to the system and it would solve the low end torque problem.

OP, your signature says that you have a custom exhaust, no resonator, and a Super 10 muffler. You have almost no restriction on your exhaust. This begs the question: what is your pipe diameter on your system? Your loss of low-end grunt could be attributed to your pipe diameter being too large.

cups said:

So there may be some system/controls that will put/leave exhaust in for re-combustion?

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As our engines are SOHC, it is "hard coded" into the design of the camshaft.

---------- Post added at 04:11 PM ---------- Previous post was at 04:03 PM ----------

Cleave said:

The 6.2L has variable valve timing, this is used specifically for exhaust emissions, not performance like the little Honda's cute little v-tec, I'm not sure exactly what it does {snip}

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The Ford system is quite a bit different than V-Tec. Ford (as well as most other car makers) uses "phasers" that use oil pressure to advance and retard the cam based on rpm / load. At low rpm, the cams are retarded for better low end power and economy and as rpm rises the cams are advanced for better power / economy.

Lmao, don't get butthurt and read only what you want to believe I'm saying instead of what I really am saying kaiser, if you knew how to read you'd know I was saying that the ford system IS NOT like the system used in Hondas, get over yourself, I know ford uses oil phasers, I know what ford says they do, and I've watched the phasers actually work on a running truck

Cleave said:

Lmao, don't get butthurt and read only what you want to believe I'm saying instead of what I really am saying kaiser, if you knew how to read you'd know I was saying that the ford system IS NOT like the system used in Hondas, get over yourself, I know ford uses oil phasers, I know what ford says they do, and I've watched the phasers actually work on a running truck

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That was a general comment directed at all who were reading this thread, not you personally.

Cleave said:

...get over yourself....

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Really? All I have provided is technical info. I have not questioned anyone's ability to read, called anyone butthurt or told anyone to get over themselves. I am not butthurt (I see nothing in my comment that would indicate as such) and I read very well, thank you very much (this is the second post in which you have questioned it).