Air Pump
02-26-2005, 03:20 PM
#1
Addict
Rennlist Member
Rennlist Member
Thread Starter
Air Pump
I am preparing to replace the clutch driven fan with an electric one and was wondering what the air pump does? The car in question is '83 Euro S, thus it has CIS injection and doesn't make it's own adjustments. So, do I need the air pump?
I was thinking I might need to keep it to pass emission tests here (the tests are pretty strict) But this is truly a guess and I was hoping some of you would have real world experience to share. Thanks in advance.
JF
I was thinking I might need to keep it to pass emission tests here (the tests are pretty strict) But this is truly a guess and I was hoping some of you would have real world experience to share. Thanks in advance.
JF
02-26-2005, 07:53 PM
#2
Inventor
Rennlist Member
Rennlist Member
Joe,
With the factory cat'verters, the air pump reduces NOx and remaining hydrocarbons in the rear section of the cat by introducing oxygen back into the exhaust stream. The front section of the cat reduces CO2 and hydrocarbons.
You'll need the pump for a DEQ visual inspection.
I can't remember the size of the belt with only the air pump, but if you do a search, it has been mentioned before.
...
I have two complete exhaust systems, one for driving, and the factory one I save for bi-yearly events.
click pic for thread
Since this picture was taken, I've replaced the rearmost of the two 12" resonators with a Flowmaster Delta 40. The sound quality and dB level is perfect now, for me!
With the factory cat'verters, the air pump reduces NOx and remaining hydrocarbons in the rear section of the cat by introducing oxygen back into the exhaust stream. The front section of the cat reduces CO2 and hydrocarbons.
You'll need the pump for a DEQ visual inspection.
I can't remember the size of the belt with only the air pump, but if you do a search, it has been mentioned before.
...
I have two complete exhaust systems, one for driving, and the factory one I save for bi-yearly events.
click pic for thread
Since this picture was taken, I've replaced the rearmost of the two 12" resonators with a Flowmaster Delta 40. The sound quality and dB level is perfect now, for me!
02-26-2005, 09:01 PM
#3
Nordschleife Master
Joe,
Depends on a number of things.
Was you car federalized completely? If you've got the dual pipe set-up all the way back and no cat then you don't need the air for that.
What kind of inspections does your state do? If you need it for that, then you need it.
Otherwise, take it off. I use my pump just to tension the belt. All the plumbing is removed. The vanes were removed from the pump as they were noisy.
One thing to consider is blocking off the inlets to the head. I tried to find and rig up plugs to no avail. Finally ordered the official Porsche plugs for a few bucks each (Doh!) These are the same as the front plugs on the block. Call 714-632-9288 and ask for 2 of 900 219 004 02 (screw) and 2 of 900 123 040 30 (seal ring) and you'll be set.
Depends on a number of things.
Was you car federalized completely? If you've got the dual pipe set-up all the way back and no cat then you don't need the air for that.
What kind of inspections does your state do? If you need it for that, then you need it.
Otherwise, take it off. I use my pump just to tension the belt. All the plumbing is removed. The vanes were removed from the pump as they were noisy.
One thing to consider is blocking off the inlets to the head. I tried to find and rig up plugs to no avail. Finally ordered the official Porsche plugs for a few bucks each (Doh!) These are the same as the front plugs on the block. Call 714-632-9288 and ask for 2 of 900 219 004 02 (screw) and 2 of 900 123 040 30 (seal ring) and you'll be set.
02-26-2005, 10:42 PM
#4
Addict
Rennlist Member
Rennlist Member
Thread Starter
Glen,
I think the car was federalized with a cat that is two in and two out. I still have it and it looks new. This unit was immediately removed and msds headers and two "test Pipes" were added to the remainder of the stock exhaust. Then, the car was registered in an area that did not require inspections.
When I bought the car, I could not get through the DEQ test with no cat. Not from visual inspection, but just too stinky. I had a new exhaust system made by Tom Cloutier that included a cat. It is a small, high flow unit and was just enough, with some "serious" tuning to pass the test. I don't know if the air pump is contirbutiing to that passing or not. I tend to think not, but can't say for sure.
Ken,
Do you think they actually check for the pump at the inspection station? In my visits there, I cannot tell.
I will attach a photo of my exhaust so you can see what I mean by small cat. I will also show you what the "test pipes" looked like on the old system. I don't think there is any hose going to the cat. only the one into one of the header collector.
I did a search and can't really say I learned anything conclusive. Lots of euro cars with the cat and airpump removed, but I am not sure any of them are in areas where the inspections are so ****.
Thanks for your thoughts on this. I appreciate the input.
JF
I think the car was federalized with a cat that is two in and two out. I still have it and it looks new. This unit was immediately removed and msds headers and two "test Pipes" were added to the remainder of the stock exhaust. Then, the car was registered in an area that did not require inspections.
When I bought the car, I could not get through the DEQ test with no cat. Not from visual inspection, but just too stinky. I had a new exhaust system made by Tom Cloutier that included a cat. It is a small, high flow unit and was just enough, with some "serious" tuning to pass the test. I don't know if the air pump is contirbutiing to that passing or not. I tend to think not, but can't say for sure.
Ken,
Do you think they actually check for the pump at the inspection station? In my visits there, I cannot tell.
I will attach a photo of my exhaust so you can see what I mean by small cat. I will also show you what the "test pipes" looked like on the old system. I don't think there is any hose going to the cat. only the one into one of the header collector.
I did a search and can't really say I learned anything conclusive. Lots of euro cars with the cat and airpump removed, but I am not sure any of them are in areas where the inspections are so ****.
Thanks for your thoughts on this. I appreciate the input.
JF