What does the smog pump do should I remove it?
What does the smog pump do should I remove it?
I have a 1987 Iroc-Z Camaro and I hear that the smog pump robs power and I should remove it but what does it do? Second question, if I remove it will my car run right?
Please help me out, Thx
Please help me out, Thx
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: What does the smog pump do should I remove it?
The smog pump blows clean air into the exhaust to reduce tailpipe emissions. It uses almost no horsepower.
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From: Mobile, AL
Car: GTA
Engine: 383 HSR
Transmission: TH-700R4
Axle/Gears: 3.42
Re: What does the smog pump do should I remove it?
It's main purpose is to take up space in my precious engine bay. Makes a good door stop though.
You can bypass it easily if removed. There is a tech article on what belt to buy and how to route it, however apeiron is right it does not take much horsepower maybe 1-2 not enough to notice, but weight and cleaniness is important to some people.
You can bypass it easily if removed. There is a tech article on what belt to buy and how to route it, however apeiron is right it does not take much horsepower maybe 1-2 not enough to notice, but weight and cleaniness is important to some people.
Re: What does the smog pump do should I remove it?
hey my car doesn't have a serpentine belt its got 2 seperate belts so can I just unbolt it and ditch the belt? and do I need to remove the cat if I do this?
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Joined: Jul 1999
Posts: 17,262
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: What does the smog pump do should I remove it?
The smog pump blows clean air into the exhaust until the engine reaches operating temperature. Once the exhaust gets hot enough, the extra air isn't required to lower tailpipe emissions and a valve opens to divert the air away from the exhaust. It's only purpose is to reduce exhaust emissions of a cold engine. Think of it as a cold engine normally runs rich. Any unburnt fuel goes out the exhaust. Extra air is added to the exhaust to lean out that raw fuel in the exhaust which lowers emissions. An O2 sensor may keep the system in an open loop longer without the smog pump.
I took mine off my truck years ago and my TBI system never knew it was missing. The downside of the pump is that once they get moisture in them, they will seize up. It uses little to no hp but once it seizes, it will eat a belt. It also adds unneeded weight to the car.
Joined: Mar 2000
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Not quite again.
Once the engine goes to closed loop control, the air is diverted directly to the cat where it supplies extra oxygen for converting CO to CO2.
If you remove the belt, block off the tubes on the exhaust. As Stephen said, they will freeze up, and if you remove the belt and leave the rest hooked up to the exhaust, expect it to freeze up. Ask me how I know.
The other thing the pump can do is crankcase evacuation. . .
Once the engine goes to closed loop control, the air is diverted directly to the cat where it supplies extra oxygen for converting CO to CO2.
If you remove the belt, block off the tubes on the exhaust. As Stephen said, they will freeze up, and if you remove the belt and leave the rest hooked up to the exhaust, expect it to freeze up. Ask me how I know.
The other thing the pump can do is crankcase evacuation. . .
Joined: Mar 2002
Posts: 587
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From: middle TENNESSEE
Car: 1989 Iroc rebuild
Engine: 355 carb'd
Transmission: 5spd
Axle/Gears: 3:08 pos for a while
Re: What does the smog pump do should I remove it?
when mine went sounded like the water pump,has that knocking kinda sound,good thing removed b4 the bearing seized!
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Joined: Jul 1999
Posts: 17,262
Likes: 168
From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: What does the smog pump do should I remove it?
The GM smog pumps need to be modified to be crankcase evac systems. The inlet is in the front behind the pulley which isn't an easy way to run an inlet hose 2. The Ford pumps are more popular since they have an inlet and outlet port.
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From: Deer Park, N.Y.
Car: 1983 z-28/SFC/bilsteins/adj.arms
Engine: 355sbc/Demon650dp/hedmanheaders/
Transmission: t-5, alum DS
Axle/Gears: 3.42 torsen posi, baer discs
Re: What does the smog pump do should I remove it?
get rid of it! it does take energy away from the engine....with age they can seize and burn up the belt! it happened to me. when i removed the belt, the car picked up some power! i still passed emissions...
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
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Joined: Oct 2003
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From: Slough, England (near London)
Car: Camaro IROC Z28 ~ 1987
Engine: 305 Tpi
Transmission: TH700R4
Re: What does the smog pump do should I remove it?
So on my 87 Tpi engine, it can just be removed and the ECU will not be bothered at all?
Not worried about the HP, but it would be nice to have better access to the engine.
Not worried about the HP, but it would be nice to have better access to the engine.
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Junior Member
Joined: Oct 2003
Posts: 35
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From: Slough, England (near London)
Car: Camaro IROC Z28 ~ 1987
Engine: 305 Tpi
Transmission: TH700R4
Re: What does the smog pump do should I remove it?
So what is the simplest way of blanking off the inlets on the manifolds? just a bolt in each hole?
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Joined: Jul 1999
Posts: 811
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From: Maple Grove MN USA
Car: 1984 Z28 Camaro
Engine: H.O. 355 NOS
Transmission: 700R4
Re: What does the smog pump do should I remove it?
While when I worked for BMW they did a test on smog pumps and they came up with a loss of .7 of 1 HP.
Auggie
Auggie
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From: Central Illinois
Car: 89' Pontiac Firebird
Engine: L03 carb Ported #87s new shortblock
Transmission: 700r4
Axle/Gears: 2.73 open
Senior Member
Joined: Jul 1999
Posts: 811
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From: Maple Grove MN USA
Car: 1984 Z28 Camaro
Engine: H.O. 355 NOS
Transmission: 700R4
Re: What does the smog pump do should I remove it?
You know I think you don't think you have to do anything because of the check valves.
Auggie
Auggie
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Joined: Mar 2009
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From: West Virgina
Car: 86 Iroc Z-28
Engine: 5.0 305
Re: What does the smog pump do should I remove it?
I doing a smog removal on my 86 Iror z mostly because of all the space they take up, im also removing the Cat, no emission controls in WV =). It can give a small amount of HP back, buck to really get some decent Hp put new headers on it.
Re: What does the smog pump do should I remove it?
Wow, you bumped a thread from 2 years ago
Good on you for using the search function though! I am getting ready to do an AIR delete also, so I have been sifting through the posts. There is a really good sticky with a pictoral guide in the exhaust forum. Joined: Jul 1999
Posts: 10,950
Likes: 26
From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Re: What does the smog pump do should I remove it?
Please keep the cat on your car by replacing it with an aftermarket "high-flow" cat. You'll keep the air clean and help keep the smog-***** from having California emissions standards in every state.
Re: What does the smog pump do should I remove it?
i also have 2 belts rather than a serpentine belt. how do i remove my smog pump? i really want the extra space in my engine compartment 
and it seems my smog pump has been dumping carbon into the combustion chamber and it is causing it to diesel a little bit. maybe its not the pump but i have replaced a whole lot of crap in my car and retarded my distrubuter and it keeps dieseling so im just trying to eliminate the variables one at a time.
any advice is appreciated!

and it seems my smog pump has been dumping carbon into the combustion chamber and it is causing it to diesel a little bit. maybe its not the pump but i have replaced a whole lot of crap in my car and retarded my distrubuter and it keeps dieseling so im just trying to eliminate the variables one at a time.
any advice is appreciated!
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Joined: Mar 2010
Posts: 135
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From: United States
Car: 1989 firebird
Engine: 350 tpi
Transmission: 700r4
Re: What does the smog pump do should I remove it?
It's main purpose is to take up space in my precious engine bay. Makes a good door stop though.
You can bypass it easily if removed. There is a tech article on what belt to buy and how to route it, however apeiron is right it does not take much horsepower maybe 1-2 not enough to notice, but weight and cleaniness is important to some people.
You can bypass it easily if removed. There is a tech article on what belt to buy and how to route it, however apeiron is right it does not take much horsepower maybe 1-2 not enough to notice, but weight and cleaniness is important to some people.
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From: Cumberland, RI
Car: 1989 Camaro RS
Engine: 305 TBI
Transmission: 700R4
Re: What does the smog pump do should I remove it?
Junior Member
Joined: Nov 2009
Posts: 36
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From: Watertown, SD
Car: 1986 IROC
Engine: 305 TPI
Transmission: 700R4
Re: What does the smog pump do should I remove it?
but yeah it really doesn't hurt or harm the engine much. my car had most of it removed when i got it, i just took the tubes off of the manifolds. if you want a little more room then it wouldn't hurt if u removed everything.
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Joined: Oct 2002
Posts: 9,067
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From: Saskatoon, SK, Canada
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi
Re: What does the smog pump do should I remove it?
They use a pipe thread, not a regular bolt thread. You have to use pipe plugs to block the holes.
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Joined: Dec 2009
Posts: 338
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From: Granite Falls, NC
Car: 1992 Camaro RS
Engine: 305 TBI
Transmission: T5
Re: What does the smog pump do should I remove it?
People need to think a little bit before removing this stuff. Very little HP is lost on a streetcar by deleting this stuff. NC used to not inspect for any of that. Now they do and so are other states joining the emissions testing and inspection. If you delete the emissions equipment, add carburetors or after market EFI without an EGR you are just asking for headaches down the road.
Re: What does the smog pump do should I remove it?
Mine was very easy on an '86. Cut the belt and remove the pump and unnecessary brackets. Unbolt all 8 of the air injectors on the exaust manifold, plug them with pipe plugs from hardware store (take one of the fittings with you that you took off the manifold). Remove hoses from coolant switch, remove and plug vacuum lines that go to diverter and carb, run straight run of hose from pvc to carb. Disconnect vacuum line to exaust valve and leave it open. I then had to unbolt air tube connected to rear exaust bolt and cut off the 1/2" tube to cat. My cat did not leak air as I thought it would, but you could throw a bolt in there if you wanted. I later removed the cat and hammered a steel rod through it until all the catylist crumbled and fell out. I then put the "empty cat" back on just in case a visual inspection. I then cut off factory muffler and bolted on a "thrush welded" exaust dumped in front of rear axle...Damn! sounds good, feels way better, runs better, and looks much better under the hood, and I can change my plugs without cutting up my hands. Don't know about codes on an '86, pulled the bulb out a long time ago. Not one problem after six months.
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From: Michigan
Car: 86 IROC Z, 92 RS
Engine: 305 4bbl, 305 TBI
Re: What does the smog pump do should I remove it?
Actually, federal law applies to all 50 states, and federal laws say you cannot remove or disable the emissions devices on any street vehicle.
Please keep the cat on your car by replacing it with an aftermarket "high-flow" cat. You'll keep the air clean and help keep the smog-***** from having California emissions standards in every state.
Please keep the cat on your car by replacing it with an aftermarket "high-flow" cat. You'll keep the air clean and help keep the smog-***** from having California emissions standards in every state.
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From: Eastern NC
Car: 85 sport coupe
Engine: 355 sbc
Transmission: 700R4
Axle/Gears: soon 4th gen 3.23 w/ Posi
Re: What does the smog pump do should I remove it?
ok, so i just cut the belt off of my smog pump. i had 3 separate belts so I just cut that. my question is, can I just take the pump off? I'm in eastern NC and don't know the laws here completely. if nothing else in theory couldn't I just take it off and then when my car goes in for inspection put it back on real fast like? or is it difficult to take off/put on?
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Joined: Dec 2009
Posts: 338
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From: Granite Falls, NC
Car: 1992 Camaro RS
Engine: 305 TBI
Transmission: T5
Re: What does the smog pump do should I remove it?
ok, so i just cut the belt off of my smog pump. i had 3 separate belts so I just cut that. my question is, can I just take the pump off? I'm in eastern NC and don't know the laws here completely. if nothing else in theory couldn't I just take it off and then when my car goes in for inspection put it back on real fast like? or is it difficult to take off/put on?
That pump does not hurt you in any way. Leave it on pass the test so you won't have to worry. If you was racing the car where you needed every ounce of power that's one thing. But if that was the case it would not be a street driven car anyway. For a street driven car it's not worth the time and hassle.
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From: Michigan
Car: 86 IROC Z, 92 RS
Engine: 305 4bbl, 305 TBI
Re: What does the smog pump do should I remove it?
In NC if you disable the emissions you will fail the inspection. That means you will not get your tag sticker until you fix the problem. Yes you can find that place that people go to in your area to get it inspected that doesn't check. BUT, NC does crackdowns and then go after the car owners. If your car passes the test again all is good if not you will pay a hefty fine.
That pump does not hurt you in any way. Leave it on pass the test so you won't have to worry. If you was racing the car where you needed every ounce of power that's one thing. But if that was the case it would not be a street driven car anyway. For a street driven car it's not worth the time and hassle.
That pump does not hurt you in any way. Leave it on pass the test so you won't have to worry. If you was racing the car where you needed every ounce of power that's one thing. But if that was the case it would not be a street driven car anyway. For a street driven car it's not worth the time and hassle.
Senior Member
Joined: Jul 1999
Posts: 811
Likes: 5
From: Maple Grove MN USA
Car: 1984 Z28 Camaro
Engine: H.O. 355 NOS
Transmission: 700R4
Re: What does the smog pump do should I remove it?
When I worked for BMW they said that smog pump losses were .7 tenths of 1 HP.
Auggie
Auggie
Junior Member
Joined: Feb 2011
Posts: 21
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From: north carolina
Car: 1991 rs B4C package
Engine: 1972 355 sbc
Transmission: 700R4
Axle/Gears: 10bolt 3.73 gears
Re: What does the smog pump do should I remove it?
i just gutted mine and she works fine. no hp loss and didnt need to get a new belt
Re: What does the smog pump do should I remove it?
Im curious how you "gutted" one as well. Ive opened one up and there isnt much to take out. The bearings actually ride on the mechanism containing the vanes, so removing it prevents you from reassembling the pulley. Solve that hurdle and you'll find the shaft doesnt go through the pump completely, so chalk up a custom shaft and bearings. By then you'll wonder why you didnt just take it off and use a shorter belt before failing visual inspection
white83, use any header with air tubes. Almost all shorties offer with and without versions
Re: What does the smog pump do should I remove it?
Thanks everyone for your input..was actually debating disconnecting both smog pumps on the 460 Ford powered family Rv when I ran across this thread..according to Bmw research that would gain 1.4 hp that thing needs every hp it can get..Ps not disconnecting my pump on my 86 Iroc 305 Tpi as I have a lonnng list of improvements to make on this relatively stock Camaro well worth saving.
Joined: Sep 2005
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Re: What does the smog pump do should I remove it?
Read through this thread https://www.thirdgen.org/forums/tech...smog-pump.html for an exhaustive discussion, complete with a few total morons coming into it and spanking off about it. You won't have any trouble figuring out who they are.
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