California emissions? I saw it on a 1990 348 out there in the interwebs... Image Unavailable, Please Login
Not just California. All cat equipped cars had air injection so it was all of USA and a lot of other countries too.
And you can buy a replacement from any automotive store for about $15. It is worth nothing, apparently.
Extra ports in the heads for the air injection rails as well. https://www.ricambiamerica.com/car-diagrams/ferrari/v6-v8/348-group/348-1989-1992/air-injection-device-motronic-2-7.html
My UK specs Non-Cat 348 also has them. It is actually not air injection, just air suction (induction), and it is active during the first 2-3 minutes of warm-up (from a cold start) to reduce emissions when the engine is running rich.
Yes, actually it is air injection. Its legal definition is air injection and technically there is no vacuum, only pressure or lack thereof so air is being pushed in under pressure.
My '89 does not have this, or i've just not paid enough attention...but both the small ports on my airbox are closed off. I also have engine # 216xx sjd
Just for interest you can see on this new very early car that the air system is missing. The ports are in the head but blanked off. Note no cats either. Image Unavailable, Please Login
No. Its a Euro car I believe Brian. As I said not all early cars. I just posted it for interest sake. If the US cars had cats then I guess they had the had the air system too.
On the 348-s, nothing is pushing the air into the exhaust system (there is no air pump). The air is sucked (from the air filter box) by the brief vacuum pulses at the exhaust ports. The non-return valves (check valves) prevent the pressure pulses of the exhaust from blowing into the air-box and allow only the suction pulses - air pulled from the air box into the exhaust port where it helps burn the unburnt gasses as they travel down the exhaust. So, there is vacuum (brief vacuum pulses) in the exhaust ports. The diagram below shows the pressure and vacuum phases in the exhaust ports, in the cylinders and in the inlet ports. The vertical scale of the diagram is in absolute pressure (psia) and the pink line shows the relative (to atmospheric) "zero" pressure (14.7 psia). Everything below the pink line is what is normally called vacuum. (EVO - Exhaust Valve Open... etc.) Image Unavailable, Please Login
Now that you mention it... the Mondial 8 that I owned during the mid 90s had an air pump. Seized, of course. I remember searching for a match-up at the local AutoZone. A GM unit if I recall correctly but am not sure if I ever found one.
So with all this said is it safe to assume this can be removed and simply plugged at the air box ports and plug the ports in the head? Assuming there is a no cat situation and no emissions testing.
I believe it can be removed without any issues. Some time ago, I had a motorbike, Yamaha 900 Diversion, which had a very similar system. I removed it and had no issues at all. The engine actually idled smoother without it.
I did the same during the 80s on the TR8 I owned. The "Smog Plugs" looked similar to this: Image Unavailable, Please Login Now they have so much more to offer. http://www.thewedgeshopstore.com/air-rail-block-off-plugs-tr7-tr8/
I'm glad I saw this thread. I hadn't even thought about removing it before this. My engine is currently out and was going to make some pipes to replace the cats, might as well do this at the same time.
