ive been through this thread and read and skimmed some parts. i have a 92 bird with the TBI 305. i want to do this but ive heard that the maifold threads are 3/8 and ive heard they are 1/4. which is it? also im broke and cant weld so what is the best/cheapest way to plug the tube going to the cat? i read just pinch it with vice grips?? really? im more of a visual guy so any pics to go along with a description would be awesome!

 

Just keep one after you remove the tubes and take it to the parts store with you to see what size to buy.

And for the hole to the cat, yea, bend it, except it's probably really hard to bend because mine was super thick for some reason. Might have to use a torch to heat it up a bit first. I drove around for a few days with it open before I just straight-piped my cat. It's just extra stinky when driving.

 

thanks for your input. i like it when people try to help instead of slamming you for doing something.

 

for the cat couldnt you just take the cat and slap some flanges on it? i took a 3 inch dynomax cat, banged the oval part round, welded 2 tri-flanges on there and made a secondary flanged 3 inch pipe so i can just remove the cat and put in the "test pipe" lol

 

Hi 91CamaroRS305. For you can bypass it and you should not worry for it. It is just okay.

 

My AIR system is almost gone. I did notice after removing it that I smelled more crap than ever before. Hold up, maybe that was my own gas or maybe a smelly truck I passed? Oh well.

 

Has Anyone from delaware on here took their Air pump off and passed the delaware emmissions tests? I just took all mine off and installed hooker 2460s and have to go through the delaware tests in october.

 

Hey Guys,

My name is Fermin and I wanted to ask a question about the A.I.R System being pulled out. Last friday i went to a mechanic that was going to install my headers well he didnt want to do it becuase of the A.I.R system. I told him to delete becuase i dont want it anymore as im running LT headers with no cats straight to my Borla Exhuast. Well i want to double check is there a way to install these headers easier then doing the whole deleting of the pulley and all that. Can i just plug the lines somewhere. Please help me as when i take it to the mechanic i wanna be able to tell them this. 1992 Camaro 5.7L L98 TPI...Also i know its been talked if you loose Hp on a 305 how about my 350?? Please help thanks

 

Seems all of these posts are mostly relevant to tpi/tbi setups. I just started this on my 4bbl 305 yesterday. There are a ton of vacuum hoses going from the carb to the various a.i.r components, do I just block these off?

-Blain

 

does anyone have a size for the plug bolts that thread into the stock exhaust manifolds in place of the air tubes on an 88 350TPI in the IROC-Z. i see that classic industries have them, but i've got a shop full of pipe plugs and bolts so i might already have them laying around.

 

Hi guys,
I've been grappling with the same issues on removing the emissions, smog stuff because I couldn't get to my spark plugs. I believe in clean air, but I also believe in a clean burning engine that doesn't smell. Personally, I think that's the most logical way to look at this. I mean if, you're burning up all the gas going into the chamber, what's left to pollute anything? Not exactly a scientific approach, but it makes sense to me. When ever one of those big jets take off at the airport, I think they put a whole lot more stuff into the atmosphere than one car can do in a lot of tries....
I just got through pulling off the tubes from my 87 305 and was able to change my plugs. I hack sawed a couple on the passenger side and just unscrewed the lines on the drivers side. I'm not a mechanic though and don't know exactly what to do with the two tubes coming up from the back of the engine. They suck air, and what do I need to do with them?? I've spent about 4 or 5 hours reading your conversations trying to figure it out and no one has really stated what we need to do with them. I think they must need some kind of filter on the end. It seems like they need to breath...

Dale

 

Jets are aproved by the FAA to fly, they emit polutants but its approved, and our emissions equiptment is required by federal law technically, its out dated but still considered a requriement. I'm not preaching here just puttin it out there

And what one the smog equiptment stopped you from changing plugs?! Try putting in some headers and doing the plugs, then get back to us and tell us your solution, I don't think you'll take a hacksaw to. Do them, I hope not atleast.

Some plugs come from the top some from the bottom, you just gotta try different angles and positions to see what works best

 

When I took off the AIR on mine I had bloody knuckles from all the BS.That snowballed into modified exaust and eventually a decision for an engine swap which I'm still doing now.To the original question..It didn't effect the way my engine ran at all.I plugged the holes in the manifolds with 1/2 inch bots and called it a day.I eventually pulled the ecu and all related wiring and behold!!!. It still ran.Now I have all mechanical gauges and I love it.No more electronic crap to foil my senses.I love a V8 with nothing but a spark,gas,oil and coolant.

 

Is there a definitive answer as to whether you can run a high flowing CAT without AIR injection? After reading all 6 pages I have not yet really seen the answer to this question. My PROM is tuned to accommodate the removal of AIR, so no issues there.

As I understand it, AIR warms up the O2 sensor until it is active (not needed in my case as I run a 3 wire heated O2 sensor) and then breaks up the carbon monoxide in the catalytic converter (in closed loop, once O2 is warmed up) which further reduces emissions.

I have no AIR injection plus a gutted cat, but I want to buy a non-AIR high flow cat to reduce emissions and keep the AIR system removed (i don't have to test for emissions, I want to install the cat just so that the air around me is better the breathe).

Can I run a high flow cat without air injection?

 

So you just put caps over the metal tubes that the air hoses were attached to? Where did you buy these caps if there special caps for it or w/e lol. I just put headers on mine and have to do this.

 

I also would like to know this

 

Just got done pulling my seized AIR pump off my car. Went with the Belt routing in the Middle picture of the Tech article (Which is basically my factory routing on my 88) and a Duralast 968K6 Belt. (96.8" belt = 2460mm Belt for those of you that dont have a US to Metric converter handy. Some manufacturers part number will show mm instead of Inches)

For reference, the Pump is attached to the Bracket via 2 long bolts that can be removed from the front of the pump. Above and Below the pump. These 2 bolts are T45 Star Drive(Torx).

As for the Catalytic converter needing the O2 Pump, It doesn't really, but having it will reduce you emissions more... Mostly when the car is cold. The oxygen being pumped into the manifold helps burn off gas and heat the Cat up quicker. The Air going directly into the Cat also helps mostly when the car is warming up as well. Once the car get to its operating temperature, the air isnt needed. I think most Gm vehicles actually went to an electric pump that only ran during open loop/cold startup in the early 90's and today, there is no air pump at all.

 

This pretty much answers my question! Thank you. The car is slightly quieter inside the cabin and much less smelly so installing the cat was a great idea just wanted to make sure everything was done properly.

 

Rich wastes fuel

 

The y pipe is it the same for the 2 styles of exhaust manifolds

My car has the 305 with the injector tubes. where as the 350 doesnt have any exhaust injector tubes will the same y pipe work on both applications

 

All Thirdgens has injector tubes. Yours was probably removed

 

my 86 stock carbed iroc- is hurtin for power: can I just remove the air pump belt? the AIR system takes power to run it, so any gain(in better emissions) from this system must be thrown off by the amount of power (gas burned carbon output) to run it. or so it seems....that the system is pointless.

My guess is that if this system worked, it would be on new cars. Ive never seen this system on any other car.


Anyway, my question is if I remove the belt- will it clog up the lines with crankcase fumes? I think they just go to the cat and exhaust manifolds, but im not sure. This motor has 160k on it and it smokes a little

there are so many replies on this, if its posted and I missed it maybe you could direct me to it. thanks

 

Yes you can you''ll need a 96 inch belt

 

In regards to the delete pulley, what happens if you disconnect/cap off everything, and leave the AIR pump in there? I've seen mixed results of doing this, some say it's fine, others talk about it seizing up. I'd prefer to just leave it in there instead of getting a new belt or a delete pulley.

 

For those of you saying our cars will run rich without a.i.r. clearly have never done it, I took mine off and it runs sooo much better now and isn't lean at all, the exhaust actually stinks less now as well.

 

IIRC (it's been awhile) The reason for running lean (I don't think it runs rich?) is that the O2 sensor sees that there is "less" O2 in the mixture, it therefore reduces the fuel to accommodate. If you adjust the PROM then it will fix the problem (although I'm sure it's hardly noticeable).

Maybe your AIR pump was seized and that's why it runs better? In any case, as proven above, it is not needed really and doesn't help much (unless you require emissions testing in your state/province) and you can just run a non-AIR cat (tube blocked off, although some cats are built with no AIR injection system in mind I believe). That's what I did and it stinks WAY less (it is not really that much quieter really than a gutted cat).

 

im kinda worrying i should get aftermarrket header with air like is
http://www.ebay.com/itm/370615087592...84.m1423.l2649
or i can without air syetem?
http://www.ebay.com/itm/82-92-Hooker...da494c&vxp=mtr

i live in mass had inpenstions test every years..

 

Yeah I meant lean, sorry. My air injection system was running perfectly fine, but it wasn't even hooked up to the cat because the PO put a non a.i.r. cat on and it still passed emissions so I ripped all that stuff out, and the a/c(don't need it in Oregon). Like I said, I only noticed an increase in performance. I've also heard that the stock programming is very rich, so leaning it out by taking out the air system doesn't seem like a bad idea. I've also checked my spark plugs and they look perfect.

 

What was your performance increase and measuring standards?

The parasitic drag on the smog pump isn't a whole lot, unless the pump is somewhat seized. The spots where it would lean out is only when the 02 is commanded to port, and we're talking such a minor different in fresh air flow.

This thread should have died years ago when we started it. It is more theory than anything.

-- Joe

 

Mass dropped emissions inspections on pre-96 (now I think pre-98) vehicles in October of 2008. While technically there is still a 'visual' inspection, I can't imagine a station really picking on a 25-30 year old vehicle for missing smog pipes.

When I lived in Mass, the attitude of the inspection stations were simply that if it passed smog on the treadmill, it was OK. I always ran headers with no air, no egr, and a single high flow CAT.

Now I live in New Hampshire, and our laws are very hot-rod friendly. We're allowed to REMOVE our CAT, AIR, EGR, and EVAP system once the car is 20 years old.

-- Joe

 

I went from being able to not chirp second to being able to chirp second, so around 10 hp just for the air injection system. overall around 20-25ish because I took out a/c and ran a shorter belt.

 

Your running the 7730? Hmm, something doesn't sound right. Without deleting the AIR in the prom the engine will most certainly surge because the air is constantly being sent into the exhaust manifolds w/the 7730, even after warmup, it is constant. Once Closed Loop is enabled, driveability suffers tremendously because the timing gets skewed because of the swinging O2's. How did performance increase in your case when the air/fuel ratio becomes completely sporadic without deleting the AIR pump in your prom...?

 

Well I couldn't tell you how, but I'm getting 2 more mpg,it accelerates faster, and now I have alternator whine so it sounds like a maggie under hard acceleration .

Edit: Also, what is a 7730? OH! and my exhaust stopped popping as much when I downshift with air taken off.

 

Haha. I love you new guys

P.S, A stock L03 with a 5 speed can chirp second and third no problem. Heck, a chevy aveo (110hp) can chirp second and third.

When you can lift both front's off the ground, is when things get interesting...

-- Joe

 

I need a tach, mine doesn't read accurately, so I'm probably 1-1500 rpms below what it says. If I had a proper tach I'd know for sure lol. I'll try and chirp 3rd on my way to class today then.

Also, the way I understand the a.i.r. injection system to work is that it warms up the cat so it can burn the exhaust more efficiently when it's cold, and it also injects into the exhaust manifolds. Mine was only hooked up to those 2 things, it had nothing running to the intake whatsoever. There is no way the car could run leaner or richer because the A.i.r. system is purely for exhaust.

 

Re-read some of the posts in this thread from 7-9 years ago. #154 by me for example.

-- Joe

 

Isn't slightly lean better than slightly rich anyway? That's why turbos are effective, they cram as much air into a cylinder as possible, so in a sense leaving the stock programming the way it is would mean more air for combustion, I don't see how that would be a bad thing if there is no sign of detonation or overheating.

 

GM did some whacky things back then, or so it was thought. In my opinion, they did what they did w/the 7730 to ensure that nothing was tampered with, because they realized owners may resort to pulling the air pump off when they are not supposed to. With most of the MAF cars that I have owned, I almost always pulled the air pump, and there was no need to disable it in the prom, and never had a problem in Closed Loop, O2's read normal. That was because w/MAF cars (7165), the air from the air pump is diverted to the catalytic converter once the engine reaches operating temperature. With Speed Density though (7730), the air is constantly being sent to the exhaust manifolds, even after reaching operating temperature, and if you look at the fuel map you see that it compensates for that very thing. A good test would be to disconnect the electrical AIR connectors only, start the engine, and wait for the engine to reach Closed Loop. Nothing will happen, it will idle fine. However, leave the AIR system completely in tact, you can even leave the electrical connectors connected too, but this time disconnect the back of the tube from behind the air pump itself so that no air reaches the system, then wait for Closed Loop to be reached after you start the engine. In this case, the air/fuel ratio will swing substantially once in Closed Loop, and you can watch it happen with a scanner...

The 7730 is the ECM for your engine. If your exhaust stopped popping by removing the air pump, then chances are you were running lean with the pump in tact. You might want to look at your fuel pressure, and/or check your injectors to make sure they are all working properly...

 

Detonation happens because of the fuel we are unfortunately relegated with, a la the hydrogen radical. With pump gas, you never want to run too lean under boost. Under vacuum, you can lean it out to get better fuel mileage at idle and part throttle, but other than that, there is no benefit to running lean for increased power...

Edit: Understand that the saying "leaning it out for more power" implies getting it closer to 14:7 (stoich) from already being in a rich state, not from already being in a lean state...

 

Alright I'm confused. Popping is caused by running too lean. But removing the air pump is supposed to make the car run leaner, but I was already running lean and it made the car run richer by introducing more air to the equation? Please correct me if I'm not accurate.

 

No, turbos increase volumetric efficiency by forcing more air than would have been forced in when the pressure differential of the piston moving downward.

The job of the ECM is to add fuel at the appropriate RATIO for the measured incoming air.

If you lie to the ECM about how much air is being measured, then your target AFR is off.

What AFR is correct is dependent upon the application. Some combos make more power at 12:1 than 12.5:1 than 11:1 AFR. Lot's of variables as to why, cooling through fuel, atomization, etc.


-- Joe

 

Popping is caused by excessive oxygen in the exhaust manifolds...

No, it will cause a lean spike because the injectors are triggered to compensate (in sync) only so often for the added oxygen content provided by the air pump. The air pump delivers air, but this incoming air is essentially "pulsed" through the exhaust manifolds, which is why the air/fuel ratio swings when the air pump is removed, the swinging is due to the O2 correction caused by the commanded values in the fueling when the AIR pump is still enabled in the prom, and this only happens in Closed Loop, not in Open Loop. Too much oxygen, as well as too much fuel in the exhaust will tell the ECM it is running lean, but that doesn't mean you will hear popping in the exhaust. However, excessive oxygen by way of the air pump on top of an existing lean condition will cause popping in the exhaust, which is why it goes away when you remove the air pump. If you need confirmation of this, check your air/fuel ratio without the air pump hooked up, it is more than likely lean...

Ideally, O2 sensors only measure oxygen content to determine your air/fuel ratio, it does not measure fuel. Unburnt fuel reads as lean, not rich. What tells the O2 sensor how rich the engine is, is the amount of oxygen it senses. Too much oxygen (including unburnt fuel) reads as lean, too little oxygen w/no unburnt fuel reads as rich, and with too little oxygen the ECM can only assume that there will be fuel left over after combustion, and that is how it comes to the conclusion of a rich condition. You thought you were running lean with the air pump in tact because your fueling is suspect. When these engines left the factory they did not run lean, but in time they become lean due to failing parts. Pulling the air pump reduced the amount of oxygen in the exhaust, which is why your popping stopped. But that still points the finger towards a flawed part of the fuel system...

 

I'm coming to an understanding that if your engine runs with a good a/f ratio removing the air system without a tune will not hurt it, but if your engine has pre-existant problems you should definitely tune it to run without the air system, or fix the problem if possible.

 

Bingo! Also, removing the AIR pump eliminates clutter, but gives no real performance gain other than a slight weight savings. Your air/fuel is your air/fuel, without or without the AIR pump, so we only need to give the engine what it wants. Correct, if your exhaust is popping, but immediately stops when the AIR pump is removed, it is due to a pre-existing problem, and not the pump. If anything, popping with the AIR pump installed should confirm that the pump is doing its job and providing additional air...

 

To paraphrase for an answer for the neverending question. You can remove your air pump without tuning the computer and suffer no performance loss and no problems, unless there is a pre-existant problem, but you could gain some mpgs or slight bit of hp

 

I removed all the AIR stuff today. It all weighed in at about 15 lbs.

 

YEA same thing i thonght so.. i were owned 1988 ford crown vic i replaced aftermarket headers passed inspection in NH and never complain abt exhuast... they saying car is old and nothing do with it..
im thinking do same thing my trans am lol..
i wonder u can help me out to replaced the header at ur shop or whatever u had.. hope u can and i can get hooker short header with y pipe too..

 

gut out all the emissions crap and put in a straight pipe. but keep all the stock parts in a box just in case of a problem arises.


my KARR has all the smog pump stuff gutted and the egr blocked off with a nice anodized block off plate.

 

Yea man. Need power sound from header lol.. I have new high flow exhuast on my car now. Good thing only need header and y pipe

 

Just wondering if it would set the engine light off with that air control not hooked up