My friend just bought a beautifull grey '03 M3. The car's in immaculate condition both inside and out. It's been lowered with coilovers. Very clean drop. Since he bought the car he's added a CAI and an exhaust. I asked him if it was from the header back and he said no...that would have been much more expensive. He said it was a 3 piece setup. Anyways I apologize for the lack of details. I'm just curious to know what kind of power gains those two modifications typically yield both with and without a chip. I sense a challenge coming soon. :buttrock

OK anybody?

probably added between 7-8hp

probably added between 7-8hp

yes, about so, and the CAI will blow the cats in due time, give it 10K to 20K miles and your O2 sensor will pop as well as your cats.

CAIs do not belong in an e46 M3. Unless it stabilizes the temp at around 210F, or unless there are NO CATS, then a different story.

yes, about so, and the CAI will blow the cats in due time, give it 10K to 20K miles and your O2 sensor will pop as well as your cats.

CAIs do not belong in an e46 M3. Unless it stabilizes the temp at around 210F, or unless there are NO CATS, then a different story.
Does that still apply if the car has an aftermarket chip?

Does that still apply if the car has an aftermarket chip?

I do not know, all I know is that if the temp gets too high on the Ms, the cats burn out, the coils go. Now if you do not even have cats and removed them entirely, then there is nothing to worry about expect perhaps a slight engine heat, hotter than usual.

Long term I do not know what will happen to the engine, but as for chip mods and anything that deals with the engine, I am staying away from it.

Thanks. I'll give my buddy a heads-up when I see him on Sunday.

How does adding a CAI increase engine temps?

How does adding a CAI increase engine temps?

CAI meaning cool air intake or cold air intake. The stock is taking air directly from the outside the engine, but air intakes like the KN takes the air that is mixed in with the cool and hot from the engine bay, thus adding temp.

When I added the KN69, the temp gauge was over 210, and then after 10K miles my cats and 02 sensor went out. Great, more power, but I need my cats, or else no pass go with the inspection and that SES light, i dont want to see that damn light.

This also happened with a few buddies of mine in Kansas...their cats blew out. Also, we had both 44K miles on our cars, so the cats were near to wearing out or not we do not know.

Now, i put back the stock and the engine temp is now below 210, and its been constant.

Again, if you dont have the cats, or do not care about the SES light popping, out, I guess who cares. Just my observations with some correlation or just coincidence, dont know.

This is BS. Cat Back and CAI with software is the way to go. Way more than 7-8 hp. Although you can keep it stock and put in a 4.10 reat dif to make it really go.

I saw my buddy again today. He said the CAI is an AFE brand or MFA or something like that. I can't remember. The exhaust is a super street or something like that. I tried my damndest to remember but I dropped the ball a little.