smog removal still not a thing?

mostsmooth

Active Member
Nov 12, 2002
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Hi all,
i am bringing my 95 gt out of a long hibernation (like, 17 years of not moving much at all, like, maybe 3 times up and down my driveway total).
the other day (a month or so ago) i replaced the belt, and because im a genius i said hey, let me buy a shorter belt and bypass the smog pump, and i did.
the car has an off road x-pipe on it so the pump is doing nothing as far as i know (unless it has a dual purpose?)
i was thinking about removing the pump altogether and the plumbing that goes with it.
so i started reading some threads here, and it seems there's more people suggesting to keep the pump on rather than remove it as theres not much benefit to removing it.

the car is over 25 years old now and does not require any inspection in my state.

the goal for the car is getting it running well again (which is surprisingly close) and then maybe slowly replace/add parts to get it to a respectable 1/4 time. maybe even put the supercharger back on it.
right now it has the usual bits and pieces, a cam, ported GT40 heads, gt40 upper and lower intake, roller rockers (and maybe a missing ground wire...)

so, i should just leave the smog pump on at least until it becomes a dedicated track car perhaps?

Thanks
 
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You should be fine removing the smog pump, but keep it and all the parts that go with it.These parts have been or will be soon discontinued,meaning big money for good stock ones. My smog stuff is all in place because I have yearly inspections,and I keep the cats on to not smell like a refinery.
 
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If you have an off-road pipe, you can remove it. You’ll free up 8lb or so and 1/2HP

keep it though. Those parts are getting harder to find.
 
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Well its theoretical purpose was to inject air into the exhaust stream (first into the back of the heads while the car is warming up to heat up the converter more quickly, and then switching over to the converter itself to get it hot enough to burn more unburned fuel and to prevent the converter from fouling). If you have the stock catalytic converters, you could theoretically shorten their lives removing the air pump, though it's doubtful (and by how much - if your car burns a lot of oil it may be considerable) as they eventually heat up all on their own.

If you've deleted cats or installed moderns cats that don't require air injection, there is very little benefit. They also contribute to overheating tubular exhaust headers (even the stock ones) and shortening their lives, so pick your poison. Air pumps are also prone to failure and lock-up when the bearings go bad, as well as a little parasitic drag, and removal will very likely have no impact on tailpipe emissions (though visual inspections may get you a fail), so again pick your poison.

Now the EGR (completely separate) does have significant impact on your NOx emissions and will cause a tailpipe emissions fail (unless you retard your timing a bit). It'll also trigger OBD codes that need to be addressed. The ECU doesn't complain much about their air pump removal.
 
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So the SN95 ECU does not check out AIR valves like the Fox 302 ECU? I rarely see them, the hoses and crossover pipe usually go away if the pump does.

It's virtually identical to the Fox. You just cap the vacuum lines that control the valves. It doesn't throw a code or anything.

Ditching the smog pump is actually a good idea. If you have ever taken one of those smog pumps apart, the reason becomes immediately obvious. Whatever :taco: designed these things needs to use a smog pump as a butt plug as far as I'm concerned. These smog pumps regularly seize up instantly, which is going to melt your engine belt, and leave you on the side of the road. You have to get a shorter belt, and then route it opposite around the water pump and crank pulley. Basically you want the belt to run straight from the bottom of the crank pulley to the alternator, so that the tensioner has some leverage on it. I think mine is an 89.5" belt, part number 895k6, or 5060895, depending on the manufacturer. I have a smaller crank pulley though, but that's a good ball park number to start with.

Kurt
 
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It's virtually identical to the Fox. You just cap the vacuum lines that control the valves. It doesn't throw a code or anything.

Ditching the smog pump is actually a good idea. If you have ever taken one of those smog pumps apart, the reason becomes immediately obvious. Whatever :taco: designed these things needs to use a smog pump as a butt plug as far as I'm concerned. These smog pumps regularly seize up instantly, which is going to melt your engine belt, and leave you on the side of the road. You have to get a shorter belt, and then route it opposite around the water pump and crank pulley. Basically you want the belt to run straight from the bottom of the crank pulley to the alternator, so that the tensioner has some leverage on it. I think mine is an 89.5" belt, part number 895k6, or 5060895, depending on the manufacturer. I have a smaller crank pulley though, but that's a good ball park number to start with.

Kurt
yeah, im already bypassing the smog pump, just debating on taking the pump off or not
 
Well its theoretical purpose was to inject air into the exhaust stream (first into the back of the heads while the car is warming up to heat up the converter more quickly, and then switching over to the converter itself to get it hot enough to burn more unburned fuel and to prevent the converter from fouling). If you have the stock catalytic converters, you could theoretically shorten their lives removing the air pump, though it's doubtful (and by how much - if your car burns a lot of oil it may be considerable) as they eventually heat up all on their own.

If you've deleted cats or installed moderns cats that don't require air injection, there is very little benefit. They also contribute to overheating tubular exhaust headers (even the stock ones) and shortening their lives, so pick your poison. Air pumps are also prone to failure and lock-up when the bearings go bad, as well as a little parasitic drag, and removal will very likely have no impact on tailpipe emissions (though visual inspections may get you a fail), so again pick your poison.

Now the EGR (completely separate) does have significant impact on your NOx emissions and will cause a tailpipe emissions fail (unless you retard your timing a bit). It'll also trigger OBD codes that need to be addressed. The ECU doesn't complain much about their air pump removal.
sorry it's a old post I'm having a issue with my EGR I keep getting code 84 and all the parts are new but the smog is gone so my vacuum lines aren't correct any tips
 
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