many mod questions

**bmwmteam** · 04-30-2009, 03:19 PM

ok iv got a 99 trans am and i want to go with a set of long tubes and a ls6 manifold in the future. i was think that i would delete the cats and just put in o2 simulators. but iv been thinking if im going to do both the manifold and long tubes couldn't i just delete the egr as well. im very confused on this subject please help thanks.

**fastfirebird2002** · 04-30-2009, 03:28 PM

Originally Posted by bmwmteam

ok iv got a 99 trans am and i want to go with a set of long tubes and a ls6 manifold in the future. i was think that i would delete the cats and just put in o2 simulators. but iv been thinking if im going to do both the manifold and long tubes couldn't i just delete the egr as well. im very confused on this subject please help thanks.

I recently put LTs on my 99 formula and went ahead and removed the EGR just make sure you have the block off plates

**Wesman** · 04-30-2009, 03:37 PM

Originally Posted by bmwmteam

ok iv got a 99 trans am and i want to go with a set of long tubes and a ls6 manifold in the future. i was think that i would delete the cats and just put in o2 simulators. but iv been thinking if im going to do both the manifold and long tubes couldn't i just delete the egr as well. im very confused on this subject please help thanks.

The LS6 manifold is sans EGR, and you can get non-emissions (EGR, AIR) headers, so yes, you can just delete your EGR by doing both those mods. Thats what I did, and it worked fine. Really cleaned up the engine bay too.

As for the O2 simms, they are hit and miss. I've seen all too many times where they don't work, because the PCM outsmarts them with some diagnostic tests and realizes that they aren't reading what they should be under certain conditions.

Your best bet is to get your LS6 manifold, non EGR/AIR headers, remove the EGR and AIR system, and have it tuned and get the EGR/AIR/O2 sensor codes deleted out of the computer. That is fail safe

**fastfirebird2002** · 04-30-2009, 03:41 PM

Originally Posted by Wesman

The LS6 manifold is sans EGR, and you can get non-emissions (EGR, AIR) headers, so yes, you can just delete your EGR by doing both those mods. Thats what I did, and it worked fine. Really cleaned up the engine bay too.

As for the O2 simms, they are hit and miss. I've seen all too many times where they don't work, because the PCM outsmarts them with some diagnostic tests and realizes that they aren't reading what they should be under certain conditions.

Your best bet is to get your LS6 manifold, non EGR/AIR headers, remove the EGR and AIR system, and have it tuned and get the EGR/AIR/O2 sensor codes deleted out of the computer. That is fail safe

Very well explained and thats what I did my O2 sims still set off my SES light so I just had them remove the codes for good when I had it tuned

**bmwmteam** · 04-30-2009, 03:49 PM

correct me if im wrong but wont not having the egr plugged in make the computer set off a code.

**Wesman** · 04-30-2009, 04:12 PM

Originally Posted by bmwmteam

correct me if im wrong but wont not having the egr plugged in make the computer set off a code.

Yes, it will.

But you can just live with the SES ligh until you get the car tuned, thats what I did, no big deal. The car runs fine, its just going to throw a code for no EGR.