Okay, well I'm going to remove the AIR pump from my serpentine setup so I can mount my alternator there using this bracket.

My plan is to eliminate the manifold AIR tubes, and run an electric AIR pump off an LT1 car to provide air to the cat. Now is where I have a few questions.

My original idea was to just wire in the pump so it runs 100% of the time feeding air to the cats. However, on our cars, stock, that doesn't happen. The diverter valve decides when to put air to the cat. So then I got to thinking and figured that I could determine which connector tells the valve to divert air to the cat and use that signal and a relay to turn the electric air pump on to pump air to the cat.

This would be easy to hide and get out of the way and open up the engine bay a bit to make my head/intake/cam swap a bit easier in the future. Does this sound like it would work well? I don't really want to get rid of the AIR system completely because from experience, the AIR connection to the cat makes a big difference in emissions, so I figure I might as well hook it up so as to not ruin my cat or anything.

I am right in thinking that the AIR tubes to the manifolds don't really do anything, right (aside from the possible PROM code to add to the O2 sensor)? The manifold tubes don't make nearly as much of a difference in emissions as the cat tube does, correct?

If that is the case, I think my idea of an electric smog pump routed solely to the cat and turned on when the computer would usually divert air to the cat would work out very well, no?

 

Why not just have the electric pump go to the diverter valve and save the headache or fixing the code? The air tubes help warm up the cat and, IIRC, help keep the temp up or stable or some crap like that. :shrug:
I do remember Trax posting something about the O2 correction for the AIR pulses into the manifolds.

 

The AIR system helps to reduce hydrocarbons and carbon monoxide levels in the exhaust by injecting air into the exhaust ports of each cylinder during cold engine operation, or directly into the catalytic converter during normal operation. It also helps the catalytic converter to reach proper operating temperature quickly during warm-up. The life-span of catalytic converter is shorten if air isn't supplied as needed.

 

Totally removing the A.I.R. system will not set a code in the computer. I have done it without a problem as well as many others.

Since you're not running EGR why run AIR or even the CAT at all? Remove everything.

 

Eh, I just bought my cat to pass emissions a few months ago, and its a high-flow model so its not really costing me any power. I don't want to deal with making a custom pipe for it either. It might not be a bad idea to do though to save mileage on the cat so it will last for my next emissions test. The EGR doesn't really have a noticeable effect on emissions for me (no NOx testing here). Honestly, if I could figure out a way to keep it, I probably would just for the hell of it, but it will help to keep the intake a lot cleaner with it gone.

I thought the AIR tubes to the manifold were only used during cold start up, which is good, that means they aren't really needed.

I think the diverter valve and manifold lines are ugly, and I want to reduce clutter for my head/intake/cam/header swap. I already have my AC gone so this will be another big step in getting the passenger side more accessible (as well as the driver's side because of the air tubes). I figure I can just wire in a relay to turn the electric pump on when the computer sends the signal to divert air to the cat.

 

You could loose the air pump or keep it. Some of our cars came without them, like my old 86 mpfi, it ran fine without one. It is made to keep the CAT working at its best and to help warm things up on cold starts. Other than that, it is not much good for anything else. IMO you gotta keep the EGR for your computer controled FI. All of out FI systems use a EGR and charcoal vapor canister. Your computer will miss out on the signal / vaccum that the EGR sends and performance / fuel economy would suffer some. My advice would be to get that EGR back and not worry so much about the air pump, unless you have to keep it to make the smog poliece happy.
just my .02$

 

EGR works currently but will be gone when I convert to the LT1 intake Like I said, it does nothing for the emissions test around here since they don't test for NOx. As for the computer, that can be fixed with a simple flag setting in the PROM.

The AIR tube to the cat made a huge difference in emissions testing in my experience (and a few others that I know around here). That's why I figured that if I'm going to keep the cat, I'll keep some sort of air injection to the cat, but it can't be from the stock pump because I need to get it out of the accessory drive. So I decided to use an LT1 pump, and because I wasn't sure if it'd be okay to inject air to the cat 100% of the time, I would wire it into the connector that tells the stock setup to divert to the cat.

When they were looking in the book for my car in the office (I had failed emissions a few times before passing the other day), I saw that the AIR system isn't even required for my model year on my particular engine (305 TPI) for some odd reason, so while its not needed for the visual inspection, it does do a lot for my cat's performance, hence the reason I'd swap the LT1 pump in.

Though, I may just remove the cat and AIR altogether until next emissions testing time comes around. That way, the cat has less miles on it next time and I won't have to spend $112 on a new one next time for emissions..just swap this one back on.

 

feeding air to the cat constantly will result in the cat getting too hot, killing it just as fast as not having any air to it at all. So, you're idea of using the valve still is a good one. My question is where would you mount the lt1 pump? After that it's just a matter of getting a relay so that the AIR valve solenoid also powers the air pump when the ECM commands it to divert to cat.

I am looking to switch from stock manifold to headers, some people here and on other sites have some really good deals on headers but they're all without air tubes and I dont think you can attach air tubes on ceramic coated ones. I'm on a tight budget so I was thinking this would be a good way to save money by getting 175 dollar (shipped) ceramic coated headers and a 20 dollar lt1 AIR pump, that would save me over 180 bucks + get rid of the stock belt driven pump. I'd still need to get the rest of the exhaust system from the headers back but ~200 ceramic coated headers + switching to an electric AIR setup sounds nice.