mikestang63
SN Certified Technician
you'll see what I mean when you take the tube off. you will just flip the ends of the tube over to the flat side and reinstall them over the hole.
correct way to delete smog off of 88 5.0?
- Thread starter rustyruststang5
- Start date
you'll see what I mean when you take the tube off. you will just flip the ends of the tube over to the flat side and reinstall them over the hole.
-
Sponsors (?)
I removed my smog pump and the thermactor tubes (no cats currently-going spun metallic.) but I kept the egr and charcoal canister
This is similar to how my car came. Half deleted smog, disabled but still present egr. My tubes were luckily blocked off. I had to deal with the vac lines on mine and clean all the carbon build up from the egr not working. Also found my pcv screen missing. Dealing with these along with adding the charcoal canister and cats helped the car a ton
That's how I did mine. I figure when I yank my motor, i'll do it the right way.
If you don't have cats on the car, OR have modern cats that do not need air injection to be fully efficient, there is no reason to keep the air pump on. Removing it generates a couple codes which do not affect engine operation, and can be defeated with some resistor packs if you elect and cap the solenoids on the pass strut tower.
But, like said, I wouldn't ditch the charcoal canister or EGR.
If you don't have cats on the car, OR have modern cats that do not need air injection to be fully efficient, there is no reason to keep the air pump on. Removing it generates a couple codes which do not affect engine operation, and can be defeated with some resistor packs if you elect and cap the solenoids on the pass strut tower.
But, like said, I wouldn't ditch the charcoal canister or EGR.
mikestang63
SN Certified Technician
The modern "airless" catalytic converters are design to work with a leaner, cleaner exhaust system that is found on newer cars with a much more advanced computer and sensor system. The 86-95 5.0 Mustang system is primitive in comparison using an old, slow 15 MHH, 16 bit computer. On top of this, most of the engines are loose, burning oil and many have air/fuel ratios purposely manipulated to run at the rich end of the range. The result of both these problems is higher than normal HC levels at the catalytic converter input.
Newer engine have tighter manufacturing tolerances that translate into lower blowby and less oil consumption in the combustion chambers. The newer generation of engine management computers are running at 150-500 MHZ or more and some are even 32 bit units. More speed, more processing power and for all practical purposes, real time engine control. All this increased processing power means that the computer isn't playing catch up while calculating the input from sensors. That sensor data is used to to make decisions about the next event the computer controls like air/fuel ratio, injector pulse width and ignition timing.
At 6000 RPM, the computer has to calculate 400 firing cycles per second. That translates into checking air/fuel ratio 400 times per second and and spark timing 400 times per second, all the while monitoring the knock, air temperature and coolant temperature sensors for signs of abnormal engine operation. That's just the very short list of what the computer is doing.
All this extra processing power results in an engine that has lower emissions, lower fuel consumption and the best air/fuel ratio for the performance demands at hand. The catalytic converters have lower HC and NO demands placed on them. Because of the lower HC levels present they don't need the extra air provided by the Thermactor Air System (AKA "smog pump"). Run one of the newer "airless" catalytic converters in the relatively dirtier exhaust environment of a 86-95 5.0 Mustang and it will coat the catalyst with unoxidized HC . This will decrease the efficiency of the catalytic converters to the point that they start to clog and restrict the flow of exhaust gases through them. By the time a decrease in power is noticed, it is too late to take remedial action to save them.
I do not disagree with what you are saying,in fact-that's one of the best,most informitive examples of converter tech I've read-but I do believe as advanced as after market technology has come since the fox era-that the manufacturers of high flow-performance oriented converters base the design of there performance/high flow converters on example/scenarios like what you laid out in your post.
As always-thanks for the knowledge @jrichker -another thing I have a slightly better understanding of
There's a thread around here that a member passed smog inspections for 5 + years with spun metallic converters all while running road courses etc consistently .
As always-thanks for the knowledge @jrichker -another thing I have a slightly better understanding of
There's a thread around here that a member passed smog inspections for 5 + years with spun metallic converters all while running road courses etc consistently .
That's probably what it looked like when it was new, but what does it look like now?I do not disagree with what you are saying,in fact-that's one of the best,most informitive examples of converter tech I've read-but I do believe as advanced as after market technology has come since the fox era-that the manufacturers of high flow-performance oriented converters base the design of there performance/high flow converters on example/scenarios like what you laid out in your post.
As always-thanks for the knowledge @jrichker -another thing I have a slightly better understanding of
There's a thread around here that a member passed smog inspections for 5 + years with spun metallic converters all while running road courses etc consistently .
The "remedial action" I wrote about is sustained high power use which generates enough continuous high temperature to burn off any buildup of HC deposits. You don't get that on the streets, highways or drag strip.
Last edited:
The air pump provides extra oxygen to work with catalyst to burn the excess HC and convert it into carbon dioxide and water vapor.
Here' s the chemistry in case you are interested...
Now for the Chemistry...
"The reduction catalyst is the first stage of the catalytic converter. It uses platinum and rhodium to help reduce the NOx emissions. When an NO or NO2 molecule contacts the catalyst, the catalyst rips the nitrogen atom out of the molecule and holds on to it, freeing the oxygen in the form of O2. The nitrogen atoms bond with other nitrogen atoms that are also stuck to the catalyst, forming N2. For example:
2NO => N2 + O2 or 2NO2 => N2 + 2O2
The oxidation catalyst is the second stage of the catalytic converter. It reduces the unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over a platinum and palladium catalyst. This catalyst aids the reaction of the CO and hydrocarbons with the remaining oxygen in the exhaust gas. For example:
2CO + O2 => 2CO2
There are two main types of structures used in catalytic converters -- honeycomb and ceramic beads. Most cars today use a honeycomb structure." Quote courtesy of How Stuff Works (HowStuffWorks "Catalysts")
What happens when there is no extra air from the smog pump...
As engines age, the quality of tune decreases and wear causes them to burn oil. We have all seem cars that go down the road puffing blue or black smoke from the tailpipe. Oil consumption and poor tune increase the amount of HC the oxidation catalyst has to deal with. The excess HC that the converters cannot oxidize due to lack of extra air becomes a crusty coating inside the honeycomb structure. This effectively reduces the size of the honeycomb passageways and builds up thicker over time and mileage. Continuous usage under such conditions will cause the converter to fail and clog. The extra air provided by the Thermactor Air System (smog pump) is essential for the oxidation process. It oxidizes the added HC from oil consumption and poor tune and keeps the HC levels within acceptable limits.
Blown88GT
Founding Member
You had to resurrect an old thread just to ask for a picture? I don't get it?
Similar threads
