I never really paid much attention to it but since I have motor out and have been swapping, cleaning and painting parts, I just have to wonder what the purpose for this part is? According to the J body parts catalog is called a "valve air inj eng pulsair". Looks to me to be some kind of muffler, because a pipe coming from the exhaust manifold goes to it and then it it gets routed back up to the air cleaner.

Umm no idea 101.My only logical guess is that it catches all the additional carbon going into the exh manifold and filters it so it does not either go unburned or clog the convertor.That is the only thing that comes to mind,being my 87 maz trk has a tube on the exh man but feeds into my air cleaner soley for FRESH air maybe to help burn up carbon or better flow.Not a filter at all.My 85 has nothing like that at all.Just a exh man and similar breather tube from air cleaner tube does about the same thing.Checked my books quick did not see anything,but had to work not totally focused after 540 miles of drvg and a 12 hr day.Go figure.

It is the air injection reaction chamber, it injects exhaust gasses into the air cleaner to reburn some of the exhaust, which lowers the combustion temps, reducing emissions (NOX to be exact).


Pat

So isn't that pushing hot air into the air cleaner? Can I just eliminate this for colder air, to get more power?

Idk about that.Being fresh air is constant into ur main tube for the air cleaner and the minuet amount of unburned gases raising the temp alot I doubt it.I do not see it adding any power really.U would be better off with a k/n filter for a small 10% gain of nothing ness.OH and leaving the part as is.Up to you I guess.

Yup 10% of 50 HP is pretty small. I just hope the new motor will be an improvement over the old one. On a brighter note it is still more powerful than the Cadillac 4.1L in the 84 Eldorado.

It is also to help for start up in the winter


1999 - Cavalier - 5speed - Exhaust - 17" rims - carbon fiber hood - the beater

Is this somehow used with the EGR valve? I was told that lowering those exhaust temps was an effort to prolong the life of the oxygen sensor. But that was on the ODB II systems tho.

sounds like a version of an EGR system to me. I would leave it and go with the K&N air filter and a nice cat-back exhaust for a little more power. If you read Pat's post it mentions it is used to REDUCE the combustion temperature.

Heck, you want power, add a used NOS 50-shot and duble your horsepower - could be fun