emissions question
10-23-10, 12:11 AM
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86 fc3s base model
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emissions question
considering removing emissions stuff. been reading a bit about it, and the more i learn about what these components actually do, the more i want to keep them in functional order. im still learning the system used on my application; stock(less than par), n/a 86 s4.
question is, i want to remove my cat conv't, but theres some sort of secondary vaccuum hose goin to it, not sure what to do about that.
also, id love to take the air pump out but dont want to remove things like egr,acv,bac..and i assume the air pump is what powers those things right?
oh, one more thing, if i didnt want to install an electric air pump for the 5th and 6th port actuaters and removed the cat and replaced it with straight pipe, would i loose too much backpressure to activate the port actuaters?
first post, kind of a newbie...im sure all sorts of similar questions came up like this...sry, bein a bit lazy to search archives, gota time frame im tryin to get a buch of stuff done within. thanks for your help you guys. much!
question is, i want to remove my cat conv't, but theres some sort of secondary vaccuum hose goin to it, not sure what to do about that.
also, id love to take the air pump out but dont want to remove things like egr,acv,bac..and i assume the air pump is what powers those things right?
oh, one more thing, if i didnt want to install an electric air pump for the 5th and 6th port actuaters and removed the cat and replaced it with straight pipe, would i loose too much backpressure to activate the port actuaters?
first post, kind of a newbie...im sure all sorts of similar questions came up like this...sry, bein a bit lazy to search archives, gota time frame im tryin to get a buch of stuff done within. thanks for your help you guys. much!
10-23-10, 10:17 AM
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There are no power gains in removing the emissions stuff (minus the cats), so it is good that you are putting consideration into it. Many people screw up their cars with botched emissions removals.
If you remove the cats, you can also remove the air pump. But it is easier to leave the pump and use it to open the aux ports. You don't want a straight pipe either, because the car will be stupidly loud. In order for your exhaust upgrades to make a big difference, you will want a good header and then a nice resonator to quiet it down.
Removing the ACV is just a block off plate, no big deal. Same with the EGR. Don't remove the BAC. It is not an emissions component and is how the ECU regulates the idle.
If you remove the cats, you can also remove the air pump. But it is easier to leave the pump and use it to open the aux ports. You don't want a straight pipe either, because the car will be stupidly loud. In order for your exhaust upgrades to make a big difference, you will want a good header and then a nice resonator to quiet it down.
Removing the ACV is just a block off plate, no big deal. Same with the EGR. Don't remove the BAC. It is not an emissions component and is how the ECU regulates the idle.
10-24-10, 03:43 PM
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thanks for the info man, i deffinetly want to keep it quiet as i can but still have a good balance of not too much or too little back pressure...y'see cause on my car(86n/a s4i think) i guess the 5th n 6th ports open via back pressure from the exhaust...so if i remove the cat you say i can remove the air pump but, doesnt that control some of the other things like the acv,egr,etc.? i would like to keep that stuff as i read they look pretty useful...i read acv is to direct air to one of three places, one of them is exhaust port, thats what it says in the FSM but doesnt specify if thats the port that requires the back pressure to open the 5th and 6th ports? also the acv directs air to main converter...so if i take the pre and main converters out, is it going to mess with the other functions the acv does?
10-25-10, 10:06 AM
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If you remove the cat, there probably won't be enough backpressure to open the aux ports. So you'll want to keep the air pump to do that.
With the air pump removed, the ACV and much of the emissions system becomes useless. So you can block off the ACV and remove the associated solenoids. EGR can be blocked off with no ill effects (Mazda removed it later...)
The ACV has the job of directing air to the main cat, to the exhaust ports, or out to an air silencer depending on what the car is doing. Without the cats, you've basically disabled the emissions system so it doesn't matter whether the ACV is there or not.
With the air pump removed, the ACV and much of the emissions system becomes useless. So you can block off the ACV and remove the associated solenoids. EGR can be blocked off with no ill effects (Mazda removed it later...)
The ACV has the job of directing air to the main cat, to the exhaust ports, or out to an air silencer depending on what the car is doing. Without the cats, you've basically disabled the emissions system so it doesn't matter whether the ACV is there or not.
10-25-10, 06:52 PM
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ok, ive been reading more in the FSM and im just tryin to put the pieces together so that this all makes complete sense to me b4 i start removing stuff....so im sorry its takin me a while to fully grasp everything...
so, i want to remove the air pump because its heavy and in the way, im just fine with getting a sturdy pulley system for the alt. ive already removed the a/c and p/s...that said, maybe you know of somwhere i can look to find out more of how to use the air pump to activate my port actuators?, cause from what i see, the air pump comes from post filter to the ACV...and i want to remove the ACV but, i read that the anti-afterburn valve is controlled by the ACV and the anti-afterburn valve is part of the deceleration system...right? so another question is, if i remove the ACV but keep in the dashpot(which both are part of the deceleration system), would the deceleration system still work properly?
also would be really nice to remove that whole spiders web vaccuum solenoid stuff...
sorry if im jumpin around a bit but also related to this topic...eventually i do want to do upgrades and the like, not sure which route i want to take yet but regardless i plan to replace my ECU with a more programable one...again not sure which type yet, further research will be done b4 i decide...but that being known(that i will upgrade ECU later) may effect this next questions answer....
in the FSM it says that the ECU controls the secondary air injection control system which involves quite a few components...if i remove the air pump, ACV, and EGR would it result in an ECU malfunction since its what controls the ACV and EGR...as far as the air pump thing goes though, if i remove it, would it mess with the AFM? lets say i block the hole, post filter, that goes to the air pump, would that create stronger air flow that would flow past the AFM and throw off the signal it sends to the ECU?
again im sorry this is confusing to me and im tryin to make sense of it all...thanks for all your help man...ive actually been lookin round this site for a while b4 i became a member and ive heard nothin but good stuff about you.(aaron cake)
i dont have access to the net all the time so its kinda hard for me to just spend hours searching for answers which i would love but i guess its not realistic yet...
is there one easy step-by-step info page on this kinda thing i can get access to? i see emissions removal topics here and there but it looks like a lot of people just rip **** out of there car after following these how to info pages and end up messing up their ride via AFR or something similar.
so, i want to remove the air pump because its heavy and in the way, im just fine with getting a sturdy pulley system for the alt. ive already removed the a/c and p/s...that said, maybe you know of somwhere i can look to find out more of how to use the air pump to activate my port actuators?, cause from what i see, the air pump comes from post filter to the ACV...and i want to remove the ACV but, i read that the anti-afterburn valve is controlled by the ACV and the anti-afterburn valve is part of the deceleration system...right? so another question is, if i remove the ACV but keep in the dashpot(which both are part of the deceleration system), would the deceleration system still work properly?
also would be really nice to remove that whole spiders web vaccuum solenoid stuff...
sorry if im jumpin around a bit but also related to this topic...eventually i do want to do upgrades and the like, not sure which route i want to take yet but regardless i plan to replace my ECU with a more programable one...again not sure which type yet, further research will be done b4 i decide...but that being known(that i will upgrade ECU later) may effect this next questions answer....
in the FSM it says that the ECU controls the secondary air injection control system which involves quite a few components...if i remove the air pump, ACV, and EGR would it result in an ECU malfunction since its what controls the ACV and EGR...as far as the air pump thing goes though, if i remove it, would it mess with the AFM? lets say i block the hole, post filter, that goes to the air pump, would that create stronger air flow that would flow past the AFM and throw off the signal it sends to the ECU?
again im sorry this is confusing to me and im tryin to make sense of it all...thanks for all your help man...ive actually been lookin round this site for a while b4 i became a member and ive heard nothin but good stuff about you.(aaron cake)
i dont have access to the net all the time so its kinda hard for me to just spend hours searching for answers which i would love but i guess its not realistic yet...
is there one easy step-by-step info page on this kinda thing i can get access to? i see emissions removal topics here and there but it looks like a lot of people just rip **** out of there car after following these how to info pages and end up messing up their ride via AFR or something similar.
10-26-10, 02:15 PM
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I suggest you LEAVE the air pump so that you can use it operate the aux ports. It isn't that heavy. Certainly not noticeable on a street car and you would have to be a damn good driver to notice the weight on the track. See the 2nd gen FAQ and Archives for info on how to use the air pump to actuate the ports.
The dashpot just keeps the throttle from snapping closed. It is independent of the rest of the system. If you remove the ACV, you essentially disable the entire emissions system (with a few minor exceptions), so yes, the anti-afterburn system is also disabled.
You can remove the full vacuum rack but proceed carefully as to not screw up the car. Search the 2nd gen forum for "color emissions removal diagram" as there is documentation.
The ECU is pretty stupid so it doesn't care that the emissions system is gone.
As the AFM directly measures airflow into the engine, removing the air pump will not mess with it's reading. One of the advantages of an AFM equipped car.
No matter how you put it, removal of the emissions system WILL effect how the car runs and you will NOT gain any power (the exception being cat removal). The effects of emissions removal will need to tuned out for the car to run properly.
The dashpot just keeps the throttle from snapping closed. It is independent of the rest of the system. If you remove the ACV, you essentially disable the entire emissions system (with a few minor exceptions), so yes, the anti-afterburn system is also disabled.
You can remove the full vacuum rack but proceed carefully as to not screw up the car. Search the 2nd gen forum for "color emissions removal diagram" as there is documentation.
The ECU is pretty stupid so it doesn't care that the emissions system is gone.
As the AFM directly measures airflow into the engine, removing the air pump will not mess with it's reading. One of the advantages of an AFM equipped car.
No matter how you put it, removal of the emissions system WILL effect how the car runs and you will NOT gain any power (the exception being cat removal). The effects of emissions removal will need to tuned out for the car to run properly.
10-26-10, 09:55 PM
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ok so...from what im reading...i cant really remove the vacuum rack, ACV, and air pump until i find a way to actuate those aux ports....
i read a post on how to do that using an air compressor, a relay, and an rpm switch some found at summit racing co.
first of all, maybe im just dumb or something, but i had some trouble makin sense of all that. i def. think a straight forward 'this is what i did' post preferably with pics would be the easiest to understand.
secondly, i dont have a whole lot of tools nor materials to tinker with some creative way to get it done.
and third, that post was like 8yrs old...there hasnt been any improvements on the idea since then to create more efficiency?
i read that post and there was a lot of jumpin around, back and forth, and different ideas thrown around, mixed with a little 'off the point' arguing...
i can kinda follow it up until the point where they determined what to do about the ports snaping open...not sure how they pulled that off.
sure the supercharge feel of them open probably feels nice but sounds a little dangerous to me considering i have a less than par stock...its 24 yrs old at this point.
ill try and find that post and link it here, not sure how that ll work out...new to forum using too...
also gona keep lookin round 4 other ideas...
thanks man, much
No matter how you put it, removal of the emissions system WILL effect how the car runs and you will NOT gain any power (the exception being cat removal). The effects of emissions removal will need to tuned out for the car to run properly.[/QUOTE]
oh yeah i forgot to ask, how would you tune that stuff out w/o a standalone or somthin?
maybe a stupid question...but i said it.
also, im sure you can understand that i would like a clean bay. but maybe i should just hold off until im actually ready to put in a computer and ****.
i read a post on how to do that using an air compressor, a relay, and an rpm switch some found at summit racing co.
first of all, maybe im just dumb or something, but i had some trouble makin sense of all that. i def. think a straight forward 'this is what i did' post preferably with pics would be the easiest to understand.
secondly, i dont have a whole lot of tools nor materials to tinker with some creative way to get it done.
and third, that post was like 8yrs old...there hasnt been any improvements on the idea since then to create more efficiency?
i read that post and there was a lot of jumpin around, back and forth, and different ideas thrown around, mixed with a little 'off the point' arguing...
i can kinda follow it up until the point where they determined what to do about the ports snaping open...not sure how they pulled that off.
sure the supercharge feel of them open probably feels nice but sounds a little dangerous to me considering i have a less than par stock...its 24 yrs old at this point.
ill try and find that post and link it here, not sure how that ll work out...new to forum using too...
also gona keep lookin round 4 other ideas...
thanks man, much
No matter how you put it, removal of the emissions system WILL effect how the car runs and you will NOT gain any power (the exception being cat removal). The effects of emissions removal will need to tuned out for the car to run properly.[/QUOTE]
oh yeah i forgot to ask, how would you tune that stuff out w/o a standalone or somthin?
maybe a stupid question...but i said it.
also, im sure you can understand that i would like a clean bay. but maybe i should just hold off until im actually ready to put in a computer and ****.
Last edited by mar3; 10-26-10 at 10:56 PM. Reason: Merged back-to-back posts...
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10-28-10, 09:40 AM
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i read a post on how to do that using an air compressor, a relay, and an rpm switch some found at summit racing co.
first of all, maybe im just dumb or something, but i had some trouble makin sense of all that. i def. think a straight forward 'this is what i did' post preferably with pics would be the easiest to understand.
first of all, maybe im just dumb or something, but i had some trouble makin sense of all that. i def. think a straight forward 'this is what i did' post preferably with pics would be the easiest to understand.
This writeup, however, should help you greatly:
http://www.rotaryresurrection.com/2n...elec6port.html
It is not quite how I would do it (first of all my wiring wouldn't look like a fire waiting to happen) but you do get the general idea.
and third, that post was like 8yrs old...there hasnt been any improvements on the idea since then to create more efficiency?
oh yeah i forgot to ask, how would you tune that stuff out w/o a standalone or somthin?
maybe a stupid question...but i said it.
maybe a stupid question...but i said it.
also, im sure you can understand that i would like a clean bay. but maybe i should just hold off until im actually ready to put in a computer and ****.
10-28-10, 06:35 PM
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**** man thanks for all your help...i was gona try and get all this done in a timely fashion b4 i dont have time to focus much on the car cause of upcoming things. but it looks like i need to spend more time planin b4 i start modin...thank u.
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