hacker-pschorr

I was wondering about that, since the 928 air pump runs all the time, controlled by vacuum.

So there yea go, to all the people who constantly bellyache about leaving it on to save the horny toads and blue spruce of the Hilbert Valley......, it's actually doing more harm than good.

Sapientoni

I plugged the tube running to the cat after removal and found the air pump gives a pressurization to the air cleaner box. It makes a noticeable difference in power boosting. The difference is that I walked away from a prepped 911SC vs. him walking away from me at about the same speed. OK, I have outed my speed secret.

Daniel5691

GlenL:

Not to hijack my own thread topic (lol) but I really do think my PO was the best ever. Identifying me as a 928 n00b, he was careful not to over-sell the car or under-sell its weak spots.
He kept careful records of everything, he told me what still needed to be done, etc etc etc. He was a Rennlist guy and encouraged me to go back and read his threads on his prior work on the 928.
He threw in a Chinese Crap-Ton (CCT) of parts,
and he still keeps in contact occasionally to see how things are going with the 928 and if I have any questions.
I have never encountered a private seller of that caliber, regardless of the purchase. And he was spot-on in his description of the car.
Can't say enough good about him.
His name's Royal Lichter, rlich8 Rennlist ID.

linderpat

I have cat delete and air pump and plumbing delete, and have not had any issues with inspection (PA). However, I also run classic plates.

James Bailey

it is the tensioner adjustment for the belt driven cooling fan....

docmirror

Not to urinate on the fire, but the EPA clean air act provides for fines for anyone tampering with, defeating, or disconnecting emission devices on cars.

The fines are substantial, if rarely enforced. Some diesel tuner company just got a massive fine recently, but I don't know if any of the owners were fined, although they could be.

BTW, I have removed the pump and lines on my 928 as well.

bureau13

Just as a CYA, any future posts I may make about deleting cats, air pumps or anything else are hypothetical works of fiction and are written for entertainment purposes only.

docmirror

That was always understood - of course.

Daniel5691

Just to be sure I am EPA compliant, I plan on installing 3 extra air pumps.

SeanR

This is the sole reason I ensure any cars that need X-pipes show up with no exhaust. Look at the one in the driveway, it has no exhaust on it and it's getting an X.

hacker-pschorr

I wonder if that has to do with the "rolling coal" fad sweeping through the diesel truck world. Many states are quickly enacting new laws to go after them.

The Fixer

Just get a shorter belt if you remove the air pump. Take it off and take the fan belt, cut it and lap it and mark what length
will work. Go to NAPA or wherever and ask they find one that length. The fan will turn just fine. I used a lawn tractor belt.

As a side note, a typical mechanical FUEL PUMP when removed and replaced
with an electric pump will liberate about 2 BHP.

I read recently in HOT ROD magazine that GM Engineers found that adding 2MM width to an alternator belt took 5 BHP from their new 10,000 rpm NASCAR motor.

That air pump and it's belt belongs in the can imho.

AO

It's ballast.

GregBBRD

You can certainly remove it, but you'd better keep it close by.

The "remove anything that has anything to do with reducing emissions" game is going to stop.....soon.....and there will be significant fines.

We're not many years away from the federal government demanding that all vehicles, in all states, be emission compliant.....especially with all the "noise" about the environment. Once they require all of the federally mandated pieces to be in place, getting these pieces is going to be a real problem, for those that removed them and did not keep them.

If you stop and think about it....it is also a great way to get millions of older vehicles (that have been altered) off of the road and into the junk yards.....which helps the economy....because people then have to go out and buy new cars.

And anyone that doesn't think the economy needs some serious help is severely out of touch.

Trust me, someone in the Federal government is going to figure this out......and the beauty of it is that they don't have to pass a single new law....all they need to do is enforce the ones they have!

SteveG

Well, we've about covered the entire speculum here. What I know in NY is that my cats were gutted on the '85 (unknown previously, so not the greatest PO here) and it wouldn't pass. Spent some time trying to figure that out. Put new cats on it and it passed, immediately. So they do serve a purpose. What you do is your own business, just know what you are doing and what the ramifications may be.