Okay, I got the Cat cleaned out, and the new flowmaster is on its way, other than that ALL is as stock as it can be. As best I can tell, everything seems to be working good, but I was wondering how bad I would be confusing the computer if I were to remove the air pump and all of the eyesore that goes with it? If the computer is still controling the carb, how bad does it need the air pump to do it? Also, how much power will I gain or loose without it?

 

I hate air pumps. I have removed mine on my 86 GTA Trans AM.
But My computer is not controlling the carb either.
I would put a good aftermarket carb on the engine that the computer dosen't controll before removeing the pump
My car even passed an emmission test without the pump but I had to have a guy put my car on an exhaust analizer and adjust the carb to get it to run clean.
Some inspection stations that are ****, will do a visiual and if they see no pump will fail you so keep the pump and brackets in your garage in case you have to bolt it back on to get a sticker. The state I am in now only does a safty check, NO emmissions!

As far as horsepower gain I have been told that the pump robs you of 5 horse power.

So If you remove it you will gain 5 horse power, Gain extra space under the hood, and lighten your car by about 40 pounds.
Hey, I have a modified 305 also, and as any 305 owner knows you must try and squeek as much power as you can out of it.

Also putting a comp cam in the 305 will wake the motor up a bit.
Once you start moding your engine you may have to tweek it here and there but that is the fun of hotrodding.
If you want to keep the car original, leave the pump in.

Good Luck....

 

THANKS for the info!! I want to leave the car as original as I can, but at the same time, like you said, I want to squeak as much power as I can out of it. I gotta say, I LOVE the pic of your motor. Thats another thing that I dont like about the bird is the damn v belts.... Where do you get the serpentine belts... Junkyard, or do ya gotta get an aftermarket kit?

 

My car always had that kind of belt system.
If you were to change yours I would go to a junkyard and remove all the parts from a camaro or firebird with them. You will need to change all your pullys. The crank pully is a real pain in the but.

Keep in mind the motor in my car is out of an 84 camaro and already was set up like it is now. I am not sure about the V-belt since I don't have one but I suspect it also runs your airpump
so If you remove the pump you may end up having to change all your pullys anyway.

As I said, if you want to keep it stock, leave it alone.
But If you want to do a bit of rodding, go for it.
There is a lot of things you can do to a 305 V8.
It is not a bad engine at all.
here is another pic of my car. Hey, I would like to see a picture of your Car....

 

Without a cat, the air pump accomplishes nothing. Might as well pull it.

 

That's not really true, since A.I.R. was around before cats. But, let's address the questions anyway.

The A.I.R. is routed to the manifolds by the ECM via the diverter valve when the engine is cold and control is in open loop - i.e., the O2 sensor isn't involved as far as the ECM deciding on mixture control. When the engine warms up and goes closed loop, the ECM changes the diverter valve state to send the A.I.R. to the cat directly. It does this so the extra air doesn't give the O2 sensor an improper amount of oxygen to sense. So, the answer to that part is that A.I.R. doesn't affect the computer one way or the other (it's the other way around). And, the computer simply sends the signals to the diverter valve, it doesn't look to see if the command is received (so no error code is sent if it isn't received).

The other question was about power gain or loss. The pump does take some power to operate, obviously, but the amount is so small that whether the pump is operating or not is inperceptable to the driver. Two summers ago I kept run data with and without the pump, and the run-to-run variation was greater than the with or without pump variation. So, don't try to use power consumption as an excuse to remove the system.

 

AIR *can* affect the computer if the diverter valve jams in the "exhaust" position... the extra air messes up the O2 sensor.

Think I've seen it happen a sum total of ONCE, though. Usually the diverter valve fails in to the "converter" or "divert" mode.

 

I removed my AIR and cat, but I kept everything together so I could put it back on if I needed to(for emissions testing) I put brass screw in plugs into the exhaust manifold where the AIR tubes went. I just moved or hid the electrical connections. I have a CC Q-jet and my car runs great. It sounds meaner and I've had no drivability problems since I took all that crap out. And I still get 23 mpg on the interstate at 70 mph! I don't think taking the pupmp off adds much power at all, but all that stuff weighs about 20 -25lbs I'd say, and the engine compartment looks a lot better. I can easily change my fuel pump from the top of the vehicle now. If you do decide to take it off, just take your time, and do a good job (ie: don't just crimp the air tubing, I've seen it done and it looks like crap, use the brass screw in plugs instead, you'll have to screw them in until only 1 or 2 threads are showing in order to have no leaks)

 

Theres ya a pic of my bird as he sits right now. Goto http://www.cardomain.com/member_page...page_id=287400 and take a look... alot more pics there and you can see why I want to leave it somewhat the way it is. But, I cant thank you guys enough on the info about the AIR pump system. I have thought ALOT about what you guys said. It makes alot of sense. I was, however somewhat undedcided on what exactly to do, but them I ran across a SUPER sweet deal on an ENTIRE exhaut system. Edelbrock headers, 3 inch y pipe, 3' pipe to replace the cat, and a Dynomax superflow muffler, and tailpipes... all for less than what I can buy new headers! Theyre used, but barely, and the whole system is off of a 3rd gen car from a fellow 3rd gen member. Too good to pass up, so I think Im gonna go that route, and remove the AIR pump and all parts so that they can be reinstalled if need be (for show or *** forbid another owner) and go with the headers and muffler. The car is so stock now that it needs all the help it can get in the power department. I've been looking at tweaking the carb a little, and other small things I can do, but I'll start with the headers, and, man, the serpentine belts sure do look nice...

 

Thats a nice clean car. Its gotta be somewhat fast as it is right now. I don't know if I would modify it....
Hey man, Put a picture of the engine compartment on your website....

 

Oh, I did not scroll down enough on your site. The engine looks great. AC and everything. I don't know man....You may want to leave that bird the way it is and enjoy it. In fact It may be the cleanest most original 3rd gen Trans AM I have seen since they were new....

 

Just wondering, but, what size screws do you need to plug the spots where the A.I.R. hoses went?

Oh, and this won't ever have adverse side effects will it?

Adam

 

Thanks for the compliment, Frank! I gotta agree with you, and that is why I've been so reluctant to even concider taking anything off of it or adding anything to it. The car truely is a rare Bird. The thing that started all this was I was driving it a coulple weeks ago and noticed that the muffler wasnt quite right. Well, to make a long story short, the FACTORY muffler and tailpipes are shot. That got me to thinking that this might be a good chance to get a little more power out of it. Even the above mentioned headers and exhaust system are REALLY pushing it for me. Most of these cars on the road today no only are not carbureated, but there isnt much original to them anymore, and that is what makes this car as rare as it is... kinda wish it had about 200k on the clock, then I wouldnt feel so bad about changing it. But one things for sure, I refuse to go any further with the mods than the headers. Anything beyond that will be limited to a K&N air filter and a super coil... that sort of thing. Hey, I dont even have the heart to remove the factory cassette deck and speakers yet...

 

I don't remember the size, but they are made of brass, and you can get them at Lowe's. Do a search on this sit and you'll find the info, thats what I did.

 

1/4" Flare plugs. Flare and only flare.

 

Could you post pics and supply details on how and what parts to remove when eliminating the AIR pump.

Thanks in advance.