Rat3d M

I was messing with my Cobb Accessport that came with the 997TT I picked up a few weeks ago, and I discovered that it currently has what appears to be a custom tune done by Boost Logic for 17psi (20psi sport mode), and catless race pipes (which the car has installed currently). I was told by the seller that the car and the Accessport only had one tune file on it currently (which I was lead to believe was the stock tune, but now apparently is a higher boost custom tune similar to the Stage 2).

So my questions are:

1. Given that the car has catless straight pipes and is not currently throwing a CEL for o2 sensors, I am guessing that the tune currently uploaded into the car has the o2 sensor disabled so it does not trigger a CEL due to bad readings from not having cats in place. Do the Stage 0, Stage 1 or Stage 2 tunes that come from Cobb have this in place as well, or am I now stuck running the custom tune file that came with the car if I don't want to trigger a CEL?

2. What is the stock boost levels for the stage 0 (or OEM) tune? I couldn't find it anywhere. Just trying to get an idea how much more boost over stock I am running.

Reason I ask these questions, is that the car has a brand new clutch, and I am not wanting to run higher boost all the time (wanted to keep it on Stage 0 for engine/clutch longevity reasons until the occasional desire for more power came about).

shadow993

Not sure about questions #2, but Mitch at Cobb can answer.

As for the 1st question, he could be running spacers or programmed the 2nd 02 to show not ready. If you have a simple obd2 reader, it will show inspection parameters readiness and will answer it for you.

The problem I ran into was I had to remove the tune to get it inspected, bc the 2nd o2 was programmed to show not ready. That's when the headache starts if the spacers still register a cat failure.

saabin

DO you have the owners manual? Id find one if you dont have it.

Stock max boost is about 1.0bar and 1.2bar in sport mode(w/overboost). Of course, these are max numbers and dependent on temp, load, etc. etc. The stock tune will hit the max boost level and then quickly bleed off some boost, which is normal for the stock tune.

Is the new clutch stock or upgraded? Hopefully with a tuned car they (you?) would have put in an upgraded clutch.

If you're worried about clutch life, you can run the stage 2 tune and just not put it in sport mode.. according to your numbers above, stage 2 non-sport boost is about the same as factory sport mode in overboost..

Yogi911

The normal cobb tunes, OTS (off the shelf) do not disable the 02 sensors.

Also the stock boost is ~13.6 in normal and like 15.1 in overboost IIRC.

Rat3d M

I don't believe he is running spacers. I looked under the car when I picked it up, and I don't recall seeing any, IIRC, all 4 o2 sensors were screwed directly into the race pipes. So my guess is the custom tune Boost Logic did eliminated the o2 sensor CEL.

I do have the owner's manual, but I don't have the car yet. I picked it up and dropped it off in Houston a few weeks ago for shipment to Germany, so I won't have it in my possession until the end of March. I've only spent less than 24 hours with the car total so far.

It seems like the Stage 2 tune doesn't raise boost levels that much. I was expecting stock boost levels to be around 9 or 10 max, so it seems that I should be okay running the Stage 2 tune. Regarding the clutch, I instructed the dealership to have Boost Logic install a Sach's 2.5 clutch kit. Whether or not they did I won't know short of dropping the transmission, but that is what is supposed to be in the car.

That's what i was afraid of (regarding the OTS tunes). I read that they do delete the o2 sensor CEL for cat delete, but I guess not. So basically I'm stuck either reverting back to a catted setup, or keeping the custom Stage 2 tune uploaded into the car? I don't have much interest in having a custom Stage 0 or Stage 1 tune done just to eliminate the o2 sensor CEL given that the car already has a custom Stage 2 tune and is set up for a good power gain/reliability ratio. I was just hoping to be able to use an OTS Stage 0 or Stage 1 tune to save on the life of the clutch a little.

At least Stage 2 boost levels aren't much higher than stock levels, so with the Sach's 2.5 kit I should be okay as long as I don't beat the ish out of the car from stoplight to stoplight (not my driving style).

shadow993

Cobb will do this if you ask , so it's very possible it's ots.

They did it for me, with a simple email request.

Rat3d M

thanks. I wasn't aware of that. I will shoot them an email and see what they say.

TT Surgeon

If you're cat less and not throwing lights, then the o2 sensors are definitely turned off/disabled. Cobb should be able to help.

Rat3d M

FYI I heard back from COBB. They stated that the only OTS tune they have that has cat delete factored in is the Stage 2. The Stage 0 and Stage 1 would require a ProTuner to make a custom tune, and it's not recommended on the 0 and 1 due to potential issues with the wastegates.

TT Surgeon

You probably have a custom tune I would guess.