i was just looking at the setup of the airpump (S4 N/A), and it looks like it just goes to the ACV. I was under the assumption that the airpump was needed to supply air to the Catalytic converter, but the air tube going to the cat connects to the back of the LIM. If I were to remove the 6th port actuators and remove the actuators, could the airpump then be removed? I guess my question is that I need to keep my cat, so If 6th port actuation isnt an issue for me, but having a cat is, can I still remove the airpump?? Thanks

 

You can remove your air pump, but your cats will suffer. The air for the cats is injected directly into the exhaust, by the ACV.

Jarrett

 

The actuators are positioned by exhaust pressure. At 3,800 RPMs, it should make 3.5 psi of pressure to open the auxilary ports.

There should be line coming from the intake manifold, to a check valve, then the split air pipe goes to the catalytic converter. To make it easier to sort out the lines, look for the line at the cat and follow it back up to the intake.

 

YEAH, if you dont have cats get rid of em

 

The air pump supplies air to the ACV, which depending on load/rpm/gear sends it either direct to the exhaust ports or to the cat via a passage in the LIM which feeds the split air pipe. If the air isn't needed it's dumped via a silencer under the RHS headlight. S4's use exhaust backpressure to operate the 6PI system, not the air pump. If you keep the stock cat you need to keep the air pump, because it requires secondary air injection to work properly. If you ditch the cat or use an aftermarket cat that doesn't need air injection you can ditch the air pump and the ACV.

 

Only use of my airpump; Catapult ammunition

 

I have a Bonez High-flow cat. It does have the little nipple to connect to the air supply tube though. Are you saying that with this cat it is not necessary to still keep the airpump? Should I contact RX7.com and ask them? I need to keep a cat to pass emissions, but would like to ditch the airpump.

 

You will not pass emissions without the catalytic converter AND the airpump and ACV. They all work together.

That airpump puts out a max of four psi. Do you REALLY think that the amount of hp to drive that airpump is going to be felt when you remove the airpump??? No is the answer.

 

I passed with NO air pump and NO AVC.. only a cat.. if you do a search on me you will see the numbers i passed with.. Dave

 

wouldn't pass California emissions...

 

If you take it off you could use it as a boat anchor.

 

That air pump weighs 12lbs. Taking those 12lbs (and probably another 2 for the ACV) is free horse power (power:weight ratio).

 

I dont have the ACV and just ran a line from the airpump into the split airpipe. Of course I did fail hydrocarbons...but that's a result of my walbro255 in the car with no fuel computer. I'm putting the stock pump back in and I feel very confident I will pass.

 

I wasnt really worried about the performance aspects of it, just wanted to remove anything unnecessary, and clean up my engine bay a bit. I will be running a midpipe but swapping back my Bonez cat when I need emissions testing (PA), you dont think it would pass without the airpump or ACV?

 

^

 

air pumps make great land fill stuffers too

 

Wrong way around. If the cat has a connection on the side, it needs air injection to work properly. Some aftermarket cats don't.

 

OK, thanks.

 

you dont think it would pass without the airpump or ACV? Its one of those SLIM AND NONE deals. Heavy emphasis on the NONE.