WHAT SMOG COMPONENTS DO I DELETE???

1992MustangGT

15 Year Member
Sep 6, 2008
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Washington State
I have a 1992 Mustang GT 5.0 which is all stock except for a cold air intake and larger throttle body and mass air meter. I want to remove all the emission/smog components from the engine to free up some horsepower. My question is can someone tell me each and every component I need to remove to accomplish this? Also tell me if there's any computer or electrical modifications I will have to make to run without the smog equipment, if any. I know I can remove the smog pump and the hoses connected to it, but that's the extent of my knowledge. What about the EGR valve, EGR vacuum solenoid, misc sensors, etc...??????? Also, since I'll be removing the smog pump, does anyone make an idler pulley to replace the smog pump? Or is there a website dedicated to explaining this process??? Eventually I want to install some shorty headers and an off-road H or X pipe (not sure which one would be better or produce more horsepower, H or X???) Your advise is appreciated.
 
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Then I won't tell you that doing so is likely illegal and will probably "free up" no additional horsepower. Even in the bad old days of smog pumps, the loss was only one or two horsepower. Taking the weight of the spare tire out of the car would improve performance more than that.
 
Then I won't tell you that doing so is likely illegal and will probably "free up" no additional horsepower. Even in the bad old days of smog pumps, the loss was only one or two horsepower. Taking the weight of the spare tire out of the car would improve performance more than that.

Well if it's not doing much for horsepower, how about gas mileage? Will it improve gas mileage? If so, how much? I know alot of guys have removed all this stuff in the past and there must be a reason for it. It wil also be nice to remove this stuff to clean up the engine compartment if nothing else. I'll keep all these components just in case I am forced to put them back on the car, so I'm not worried about legality issues. I'm just wanting to free up some horsepower, clean up the engine compartment and most important, hopefully improve gas mileage. Your thoughts???
 
the only smog components on a 5.0 engine that will rob you of HP are the cats...

everything else is fine. You'll just run into trouble with engine codes removing them.

Time to pony up the cash for some real mods if you want to go faster.
 
I agree, the smog equipement really isn't hurting anything. In some cases like the EGR it actually can help fuel economy instead of hurt it. Also, you won't pass inspection since they visually check for these items. I would recommend leaving that all alone. Maybe get some high flow cats or gut them and see if it passes.

Also, if you do remove all this stuff and then sell the car, the next owner will have the headache of getting it right again.
 
it's against federal smog laws to remove smog equipment.

If it's illegal to remove smog equipment, then why do companies make h-pipes without cats for street cars? You would think it would not be profitable for companies to make these components if they could not sell them because of smog laws; however, there are tons of these parts from every aftermarket company and it's one of the most popular mods to do to free up horsepower. What am I missing here?
 
the disclaimer that says not legal for sale on pollution controlled vehicles.

Why to Bong makers make pipes and bongs for Weed when it's obviously illegal?

They could care less...it's illegal to install the pipes, not to sell them.
 
the disclaimer that says not legal for sale on pollution controlled vehicles.

Why to Bong makers make pipes and bongs for Weed when it's obviously illegal?

They could care less...it's illegal to install the pipes, not to sell them.

Exactly.

What I don't understand is the persistence of the belief that anti-pollution equipment robs huge amounts of power from modern engines. Even belt-driven smog pumps only cost 1-2 horsepower, and today's engines, for the past 20 years or so, use computer-controlled fuel systems to achieve cleaner exhaust. This results in better performance all around. Now there are performance-enhancing computer upgrades, but they are meant to improve the operation of the PCM, not destroy it.
 
A lot of people did this sort of thing back in the 70s and 80s when engine compartments were covered with vacuum lines and wires connecting the various sensors and switches that constituted emission controls of that era and made tasks like removing an air cleaner a major project. I did this myself on two vehicles I owned back then, even let the pellets out of the catalytic convertor on my 75 Firebird. The result: No real difference in driveability or performance. It did, however, make it more difficult to sell or trade in these vehicles. Lesson learned. Things got better in the 80s and 90s with electronic controls. Manufacturers learned how to get good performance, mileage and clean exhaust. Leave it alone.
 
Well if it's not doing much for horsepower, how about gas mileage? Will it improve gas mileage? If so, how much? I know alot of guys have removed all this stuff in the past and there must be a reason for it. It wil also be nice to remove this stuff to clean up the engine compartment if nothing else. I'll keep all these components just in case I am forced to put them back on the car, so I'm not worried about legality issues. I'm just wanting to free up some horsepower, clean up the engine compartment and most important, hopefully improve gas mileage. Your thoughts???

removing smog components will not gain you any poer for fuel economy. these things have been fully integrated ever since they were first required back in the mid 60's. some people have claimed that they made more power, or got better fuel economy by removing the smog components, but they dont tell you that they made other changes at the same time.

the only smog components on a 5.0 engine that will rob you of HP are the cats...

everything else is fine. You'll just run into trouble with engine codes removing them.

Time to pony up the cash for some real mods if you want to go faster.

the ford catalytic converters are much higher flowing cats than the GM style since ford uses a honeycomb design rather than pellets. the only restrictive part of the ford cats is the inlet and outlet, and since the early 80's even those have been improved.

If it's illegal to remove smog equipment, then why do companies make h-pipes without cats for street cars? You would think it would not be profitable for companies to make these components if they could not sell them because of smog laws; however, there are tons of these parts from every aftermarket company and it's one of the most popular mods to do to free up horsepower. What am I missing here?

the non cat H pipes were sold originally as test pipes to check and see if the cats were causing problems. what a lot of people did was run "long term tests" using the H pipes to the point that congress outlawed the use of said pipe on cars that are driven on the street. as indicated they come with the "for off road use only" restriction.

in the end it is illegal to remove ANY smog components from ANY car that same with them. if you do remove them, and get caught, the fines are quite stiff.