Smog pump discussion?
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Smog pump discussion?
I have too much time on my hands today...Does the smog pump inject air into the exhaust manifold or draw exhaust from it and inject it into the cat? Wondering if the pump could be modified to inject more air into the system, diluting the exhaust emissions to run a hotter cam? Is this over the top or do I need to see a shrink?
nevermind, I think I know the answer to that one...
nevermind, I think I know the answer to that one...
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
to answer your question:
1) The AIR injects fresh air into the manifolds and cat.
2) This is only done when "needed" as determined by the ECU. Normally, during startup.
3) The only exhaust gases being reused are EGR.
4) The damned pump sucks up 5hp as it is... think about it.
5) Sure, stop diverting any air into the manifolds and pump it all into the main cat, when needed. I would be curious to see if there is a difference.
1) The AIR injects fresh air into the manifolds and cat.
2) This is only done when "needed" as determined by the ECU. Normally, during startup.
3) The only exhaust gases being reused are EGR.
4) The damned pump sucks up 5hp as it is... think about it.
5) Sure, stop diverting any air into the manifolds and pump it all into the main cat, when needed. I would be curious to see if there is a difference.
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
I'm not following-The ECM controls a valve that regulates air pumped to the smog rails? Would it be possible (not legal, I know)to modify the vein in the pump to pump more air through on a more constant basis-Say, lower/idle speeds where you might encounter overlap from a largert cam...See where I'm going with this? Could the ECM or chip be programmed accordingly? It seems this would keep a car "legal"and still be able to run a hot cam. 
Drifting
Joined: Feb 2004
Posts: 1,277
Likes: 1
From: Santa Maria CA
i know alot of guys on here who's states don't have smog laws would say junk the pump! but,we can't because we are in california and the smog laws are very strict. 
the topic in a nutshell is saying,"lets make a home made cheap turbo out of smog pumps!".....i kindof like it
J/K!
i don't think in any way it could be made into a power adder but as far as smog goes making the pump more efficient ISN'T a bad idea
the topic in a nutshell is saying,"lets make a home made cheap turbo out of smog pumps!".....i kindof like it
J/K!i don't think in any way it could be made into a power adder but as far as smog goes making the pump more efficient ISN'T a bad idea
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by cuisinartvette
I'm not following-The ECM controls a valve that regulates air pumped to the smog rails? Would it be possible (not legal, I know)to modify the vein in the pump to pump more air through on a more constant basis-Say, lower/idle speeds where you might encounter overlap from a largert cam...See where I'm going with this? Could the ECM or chip be programmed accordingly? It seems this would keep a car "legal"and still be able to run a hot cam.
To what end? I donno... but what about a simple manual override? One that turns them on during say, emissions testing???
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Oh, another thing. The air pump does most of it's work at startup... to help light off the cats faster. Now, if you pump air into the main cat after startup, be ready to deal with more heat there.
Pro
Joined: Jan 2004
Posts: 707
Likes: 0
From: Syracuse Utah
I see where you are going. Your theory is correct. Emissions are measured in parts per million (PPM), and yes indeed if you inject more air there will be fewer emissions particles in any given sample.
Next part: as mentioned above, the air pump is mostly used at startup to get the cats going. Once going, my pump (94 electric pump) pretty much shuts down. I think on older belt driven pumps it just diverts overboard. It may be possible to always have your pump running at idle for emission testing, but it may also overheat your cats. I'm not sure. Give it a shot and see what happens.
Next part: as mentioned above, the air pump is mostly used at startup to get the cats going. Once going, my pump (94 electric pump) pretty much shuts down. I think on older belt driven pumps it just diverts overboard. It may be possible to always have your pump running at idle for emission testing, but it may also overheat your cats. I'm not sure. Give it a shot and see what happens.
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