Let me respond this way. I have not done the kinds of dynamic testing from which you are looking to see data. Ford did that when they designed the systems. The purpose of the systems is to make the Federally mandated (and that would be the demands of "we the people" if you stop and think about it) emissions regulations for the model year of the vehicle in question. So, whether you agree with your fellow citizens that clean air is a good idea or not, that is the line by which Ford (and every other auto maker) has to abide. (If you happen to be in the minority on this political issue I would suggest you get to the polls more often and not tirade about it here).
So, with that said, I can tell you this. The systems have gotten exponentially better and less restrictive over time. Considering that the Federal Standard (OBD-II) system is a direct derivative of Ford's EEC-IV system (because Ford pioneered the idea of integrating rather than slapping on extra contraptions to reduce pollutants) it is a good bet that the system works pretty well and does as little as possible to inhibit performance given the technology available at the time of the design. The EGR and Thermactor systems basically disengage when the demand for performance is "felt" by the computer. EGR and Thermactor emissions are dropped out in favor of fuel delivery and timing adjustment as much as feasible given the standards set down by the Fed. Trust me, when I tell you that no auto maker EVER sat there trying to figure out how to take performance away from their products. They throw gobs of money at making vehicles that appeal to as many people as possible. The need for improved emissions and reductions in greenhouse gasses has spurred the return to alternative fuel vehicles and electric vehicles (and no, none of the AFVs we have today are completely new ideas).
The onboard computer will basically ignore input from the EGR and Thermactor if the need for power is "felt" (typically in response to throttle position and manifold pressure changes). However, at cruising speeds and when the engine really isn't working that hard to maintain the vehicle's velocity, the Thermactor and EGR roll in and start scrubbing away at the extra crud that the engine is belching. The nay-sayers either don't believe (or don't want to believe) this but its true. Because if those systems were just "always active" why would you need all the damned sensors and control devices connected to a microprocessor to calculate, recalibrate, and regulate them all? Think long and hard about that.
If you want to know the single most likely culprit when it comes to power and performance-robbing emissions equipment, look to your old, (probably cracked internally) catalytic converter or any other faulty part of your exhaust system. Exhaust restrictions harm more engines and rob more performance than just about anything. Why? Well that's easy, how many sensors and control functions are there on the exhaust? One, maybe as many as three, and all in the form of a completely passive (at least mechanically) HEGO sensors. The best a HEGO sensor can do is tell the computer, "Hey, there's too much fuel in this here exhaust...burnin' my eyes... might wanna back off the liquid diet and just breathe the air for a bit!" To which the computer will respond however, no matter what the ratio of crud-to-air in the exhaust, there is absolutely NOTHING to "tell" the computer, "Hey, er, um, feelin' a lil' constipated here. Can we slow down on the eating?.... all this rich food could stop me up and cause some damage."
In the end, (pun intended) it makes no difference what is happening on the inbound side. If the engine cannot "exhale" as well or BETTER than it "inhales", you will lose fuel mileage, throttle response, and in really bad cases, burn valves and kill rings.
Yeah, it can be a PITA keeping Thermactor and EGR systems functioning properly and yes, when they don't, it will adversely affect performance. But if they are kept in good working order, they will scrub the crud your truck produces much better and all without noticeable detriment to fuel economy or performance.
This response is going to get arguments about computer chips and modifications etc. Listen, the question wasn't about what MODIFICATIONS would do for the performance, the question was, directed towards "Will removing something help?" And in truth, with a stock vehicle, keeping it and the onboard systems all functioning properly will offer the best overall performance. Start a new thread if you want to talk about how ADDING or REPLACING things that attempt to alter performance or functionality can change things.
I have no idea if this will help but it is the most appropriate response I can muster given that I have and always will support the idea that performance can (and frankly should) take a back seat to our children being able to live on a planet and work on their own cars in their own garages long after we are gone without special breathing apparatus. (That is my little tree-hugger speech).
So, with that said, I can tell you this. The systems have gotten exponentially better and less restrictive over time. Considering that the Federal Standard (OBD-II) system is a direct derivative of Ford's EEC-IV system (because Ford pioneered the idea of integrating rather than slapping on extra contraptions to reduce pollutants) it is a good bet that the system works pretty well and does as little as possible to inhibit performance given the technology available at the time of the design. The EGR and Thermactor systems basically disengage when the demand for performance is "felt" by the computer. EGR and Thermactor emissions are dropped out in favor of fuel delivery and timing adjustment as much as feasible given the standards set down by the Fed. Trust me, when I tell you that no auto maker EVER sat there trying to figure out how to take performance away from their products. They throw gobs of money at making vehicles that appeal to as many people as possible. The need for improved emissions and reductions in greenhouse gasses has spurred the return to alternative fuel vehicles and electric vehicles (and no, none of the AFVs we have today are completely new ideas).
The onboard computer will basically ignore input from the EGR and Thermactor if the need for power is "felt" (typically in response to throttle position and manifold pressure changes). However, at cruising speeds and when the engine really isn't working that hard to maintain the vehicle's velocity, the Thermactor and EGR roll in and start scrubbing away at the extra crud that the engine is belching. The nay-sayers either don't believe (or don't want to believe) this but its true. Because if those systems were just "always active" why would you need all the damned sensors and control devices connected to a microprocessor to calculate, recalibrate, and regulate them all? Think long and hard about that.
If you want to know the single most likely culprit when it comes to power and performance-robbing emissions equipment, look to your old, (probably cracked internally) catalytic converter or any other faulty part of your exhaust system. Exhaust restrictions harm more engines and rob more performance than just about anything. Why? Well that's easy, how many sensors and control functions are there on the exhaust? One, maybe as many as three, and all in the form of a completely passive (at least mechanically) HEGO sensors. The best a HEGO sensor can do is tell the computer, "Hey, there's too much fuel in this here exhaust...burnin' my eyes... might wanna back off the liquid diet and just breathe the air for a bit!" To which the computer will respond however, no matter what the ratio of crud-to-air in the exhaust, there is absolutely NOTHING to "tell" the computer, "Hey, er, um, feelin' a lil' constipated here. Can we slow down on the eating?.... all this rich food could stop me up and cause some damage."
In the end, (pun intended) it makes no difference what is happening on the inbound side. If the engine cannot "exhale" as well or BETTER than it "inhales", you will lose fuel mileage, throttle response, and in really bad cases, burn valves and kill rings.
Yeah, it can be a PITA keeping Thermactor and EGR systems functioning properly and yes, when they don't, it will adversely affect performance. But if they are kept in good working order, they will scrub the crud your truck produces much better and all without noticeable detriment to fuel economy or performance.
This response is going to get arguments about computer chips and modifications etc. Listen, the question wasn't about what MODIFICATIONS would do for the performance, the question was, directed towards "Will removing something help?" And in truth, with a stock vehicle, keeping it and the onboard systems all functioning properly will offer the best overall performance. Start a new thread if you want to talk about how ADDING or REPLACING things that attempt to alter performance or functionality can change things.
I have no idea if this will help but it is the most appropriate response I can muster given that I have and always will support the idea that performance can (and frankly should) take a back seat to our children being able to live on a planet and work on their own cars in their own garages long after we are gone without special breathing apparatus. (That is my little tree-hugger speech).
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