Jadz928

Well, I'm ready to remove my smog pump, and I have a few questions:

What plumbing do I remove? Can I remove all the plumbing (smog pump related) shown in the pic below?

- Sean79 5spd wrote:
"Actually the only line that need to be capped is the small vacuum line that goes to the valve three way valve. The hose from the air pump to the metal pipe on top of the cam cover should be removed to avoid it getting caught in the AC compressoer. The balance of of this sytem right up to the check valves at the exhaust system can be left in place or removed, up to you."
Where is this small vacuum line Sean is referring to?

Note: since my car originally didn't have a smog pump, and one was added upon fedralization; it is possible the system is not stock.
Also, I have no CAT, never had one.

Thank in advance!

Big Dave

Very good question, Jim, and one that I'd like to hear the answer for, too. I know that two other guys in the area have eliminated the smog pump recently after finally locating the right belt to just turn the fan (it's a belt from a lawnmower I believe). Cats are an endangered species 'round these parts.

Weissach

Yup, I take them of all my 928s. It's no big deal.

Richard S

Jim, I can take a look tonight at my set-up for you. The 84 Euro S motor I installed came with a smog pump and related plumbing, however it isn't needed on the 1980 car the motor is in. 1980 didn't have a smog pump, so California doesn't require one to be there. I removed the pump, and basically just plugged up the tube/hose behind the cam tower....I think that is what you circled. I left all the plumbing back there in case the pump ever has to be re-installed. I think mine has a Ford 3-way vacuum valve that yours does not....it is located at the end of the pipe along the top of the cam tower...in your picture it would connect the pipe to the circled hose. I think I removed and saved all that stuff, I'll check later. I belive Sean would be referring to that kind of vacuum valve. Hope this can help. Let me know if you have any questions or need pics.

Rich

Sean79 5spd

Jim, the vacuum line I was referring operates a valve which sits on the firewall end of the metal pipe running along the top of the cam cover. This pipe receives air from the air pump on one end. This air is then directed by the three way valve (based on vacuum condition) to either the air intake port at the exhaust or to the air cleaner. Basically all the plumbing can remain, including the small vacuum line.

Big Dave

This may be a silly question, but how hard is it to remove the smog pump? What stuff is in the way? My cats are long gone and the pump has been pushing air for no reason for about 6 months. It's time to eliminate it, but I've been too lazy to tackle removal yet.

GlenL

I've removed all of the plumbing from my Euro S. That leaves two holes on the back of the heads. I've used some hardware from the plumbing section of Home Despot to seal them but have realized that the holes are likely the same as on the front and am getting the "real" plugs.

I exchanged email with someone (damn synapses) who just left it all on and relied on the one-way valve to essentially seal the system. The vacuum line controls the air flow and is not providing signal.

So that leaves the pump. I recently disassembled mine and removed the pump flaps. Now it's just a belt tensioner.

PorKen

The air pump has only one long bolt and one short attaching it to the engine.

The pipe and bypass valve shown in the first picture can come out. Make sure to plug the airbox connection.

I would not count on the one-way valve to seal, it probably leaks if original.

Once the air pump is removed, and if you do not have cats, but do have air injection into the exhaust, you can run a hose from the oil fill cap to the one-way valve and have a crank vent!

borland

What's the life of a catalytic converter without a smog pump installed?

Those extra unburned hydrocarbons entering the cat must not make it's job any easier.

Tom M'Guinn

What years had a smog pump in California?

Richard S

1980 was the only year without a smog pump.

Rich

Jadz928

Well, I removed the smog pump, and related plumbing. Pretty straight-forward. Thanks everyone for the tips.

GlenL, have you ordered those caps for the back? Do you have a p/n?

Mark K, you mentioned to cap of the btm of the airbox. Is it possible to just run a hose from the airbox straight to the piping at the rear of the cam towers?

Sean, I found and plugged that small line.

When I started Chewy... btw, it is amazing how smooth it sounds without the viscous fan running (been deleted). I checked the air pressure (by touch) of the pipe at the rear of the cam tower. There didn't to be any +/- pressure. Seemed neutral. Car was running smoothly. Tho, I will plug it ...or route it to the airbox? (I'm referring to the hose labled "A" in my first pic)
Btw, does anyone need an air pump (rotated freely, w/o noise)?

Thanks for all your help!!

GlenL

Jim,

I ordered those caps from my favorite Anaheim-based retailer yesterday: P/N900 219 004 02 at $3 apiece.

There is a sealing ring for them too: P/N 900 123 018 30 at $3.80 apiece

I chose to not order the crush rings. I've got a fair collection of rings but may put on some sealant or put them in without anything.

toofast928

borland wrote:
What's the life of a catalytic converter without a smog pump installed?

Not very long. The function of the air pump is to pump additional air to the cat converter in order to increase the burning process and heat up the cat. With a cat never at operating temp, it will clog. So remove air pump, remove cat converter == HP!
You'll be amazed how much less heat enters the cabin and engine compartment when the converter is gone.

justin

How much HP are we looking at with the pump/converter delete? Can you feel the difference?