Hi guys

I'm thinking of deleting the ACV for a number of reasons including top feed fuel rail, non sequential setup and rats nest delete. I've done a myriad of searching but not seen anything similar to this yet (bar cewrx7r1's single turbo setup - which lacks the detail I'm seeking)

However I'm thinking of keeping the air pump working as:
1. I don't mind the air pump look in the engine bay - not fussy on deleting it
2. I'm a bit of a greenie at heart and like the idea of a clean idle without excessive pollution
3. I don't want to spend additional money on idlers and risk excessive bearing and water pump wear adding to more $ in the future... I want to save my $ for more fuel and driving time!
4. Not get the reported idle and stumble problems of a complete removal

So all that stated, I'm thinking of a simplified air pump setup

Any ideas on why this setup wouldn't work?




ACV removal, keep air pump

So questions I have for the pros:

Hopefully this post can be helpful to others as well :-)

 

Not as simple as your drawing. The air pump is engaged via a relay. The air pump pulley free wheels until power and ground are given to the magnet behind the pulley that engages the clutch for it. The ACV directs the air using a number of solenoids and vacuum lines to either the exhaust manifold before the o2 sensor, to the catalytic converter, or to the relief (the air box). When directed to the exhaust manifold, it "tricks" the o2 sensor reading at idle. When directed to the cat, it improves the efficiency of the cat. Your options are either A: keep the air pump 100% installed and all vacuum lines and solenoids ran as is or B: removed the air pump, all tubing and solenoids, the ACV and run an idler for the air pump. There really is no "in between". Removing the air pump entirely requires an aftermarket ECU and a retune.

Matt

 

Thanks Matt.

I have heard about some people deleting some of the acv solenoids in a part delete... but I can't remember where I read this now.

 

Being single, the setup does not have a port to allow the air pump air to flow into the exhaust as the twins did. But that was to trick the O2 sensor into a leaner reading near 14.7. Since I was initially running 850 bored out to 1200 secondaries, the ACV was still there and working. Thus a different hose was used to attach the air pump output to the stock ACV input pipe.

The ACV outlet pipe was routed into a pipe welded into the midpipe.
My setup did not use the O2 feedback system to control emissions. This setup was made just to pump air into the MP to help burn off any residue hydrocarbons. It actually made the exhaust smell cleaner.

When I went to larger secondary injectors and had to remove the ACV. Thus I routed the air pump outlet directly to my MP air pipe.

The air pump was controlled by the PFC just as it is when stock. It does clean up the exhaust some as I said earlier.

Your idea will work.

 

So wait. Do you want the air to go to the cat or to the exhaust ports? In stock form the air usually goes to the exhaust ports. It gets drawn back into the intake stroke during overlap to stabilize combustion.

 

Awesome, thanks for that detail - that helps a lot and clears up some of the confusion my end.

 

I want it to go to both. I was thinking to put a smaller hose to the exhaust ports, with the majority getting delivered to the 3 way catalytic converter.

 

So in summary:

1. If I want to pump air into the exhaust, then I need the o2 feedback system which requires the ACV and everything else, hence what Mrmatt3465 stated in post #2. So answering my own 1st question - a smaller line to the exhaust manifold is a wasted effort.
2. Airpumping into the Cat is all good in the hood :-)
3. It's a relay that activates the air pump not a solenoid dumbass!