[mg4734]

Just got a Cobb accessport, and plan to get some catless downpipes soon. I currently do not have plans to upgrade the filter (besides maybe a drop in filter) and I won't be adding an intercooler for at least a year. I'll need the car to be able to pass emissions, so I'll need a dpfix and a tune (cobb)

So my question is that since my only bolt on mod will be catless downpipes, is it really safe to run the stage 2 maps that support downpipes? Is there a way to get rid of the CEL with the Cobb for the downpipes besides running stage 2?

sorry if this is a noob question. I searched thoroughly for an answer, forgive me if I missed it in an ancient thread. Cobb's website says for stage 2 downpipes are required, but it doesn't say if it clears downpipe codes in lower stages. Thanks in advance

[foghat]

If you get down pipes, why would you run a stage one map? Run the map made for your mods and fuel.

Cobb lists what maps work with what mods on their site.

http://www.cobbtuning.com/BMW-N54-Ac...maps/bmw/IJE0S

You should run any of the Stage 2 maps. If you have 93 octane run Stage 2 Aggressive.

[AZBimmer]

Delete

[E90Company]

Yes. Run Stage 2 when you get them.

[mg4734]

Ok, thanks. Would it be able to clear the downpipe codes if I ran stage 1 though? I won't always use a 60-100hp increase, so if I can use stage 1 to reduce the demands on the motor when I don't need extra stage 2 power that would be ideal.

Edit: my main concern is running too much boost for having just downpipes. I want to be on the safe side here, but be able to get rid of the CEL associated with the downpipes. Cobb says stage 2 sport tops at 11psi, and aggressive tops at 14.5. I have 93 octane fuel, but 14.5 sounds like too much without other mods considering stock is 7-8psi.

[E90Company]

Originally Posted by mg4734

Ok, thanks. Would it be able to clear the downpipe codes if I ran stage 1 though? I won't always use a 60-100hp increase, so if I can use stage 1 to reduce the demands on the motor when I don't need extra stage 2 power that would be ideal.

No it won't. That's why they have the Stage 2 maps, Stage 1 maps weren't created for downpipes. Also that's not the way tuning works. Run Stage 2 maps and lay off the pedal unless you want the power.

[mg4734]

Originally Posted by E90Company

No it won't. That's why they have the Stage 2 maps, Stage 1 maps weren't created for downpipes. Also that's not the way tuning works. Run Stage 2 maps and lay off the pedal unless you want the power.

Ok. Tuning noob here if you couldn't tell. Thanks for the response.

[ShaneN.]

so with fmic and downpipes you'd run the stage 2? how much max boost on stage 2 sport versus aggressive? and what kind of power would you be making roughly on stage 2 sport or aggressive? i have 94 all around me but it can get below freezing around here so i feel like running 94 on a 91 tune would be a bit of a safety net. freezing temps, nice cold air and sea level all seem like recipe for disaster and maybe running 94 would give it a bit of a buffer zone? i'm not even sure how it works, i just remember my blown cars certainly making more power and boost when it was cold out.

also, are these tunes safe for us canadians with our gas not being exactly the same. and do these cars have any kind of safety feature to shut down at the sign of detonation. or do you just datalog these canned tunes and hope for the best (i'm not sure if they're all the same or if they're slightly customized based on where the customer is)? i'm wondering if the stage 2 aggressive 93 tune which would be safe to run on canadian 94 octane. apparently 92 us gas is higher Ron rating than our 94, ( as tested). just the other day i heard a local guy with a tuned switzter gtr has to pop across the border to the states to fill up since his car was tuned on US gas to avoid det.

[tennis_pr0]

Looks like they require dp for stage two, and recommend intake and CBE. I think maybe you would be better running stage 1 aggressive since you don't have an aftermarket intake or CBE. Im still a noob but this is the info I gathered from the COBB website.

[N8N]

I don't think that the Stage 1 maps will clear catless DP codes whereas Stage 2 will. best bet is to just ask Cobb but I'm pretty sure with DPs you need to run a Stage 2 tune otherwise you'll be looking at a CEL all the time.

[mg4734]

Stage 1 doesn't clear codes for downpipes, have to run stage 2. Alternatively you could run a stage 1 map and run a BMS dpfix full time, but I've read that leaving dpfix installed isn't good for fuel ratios?

[enrita]

Just open stage 1 map with ATR and disable those codes (next question: what is atr?)

[mg4734]

Originally Posted by enrita

Just open stage 1 map with ATR and disable those codes (next question: what is atr?)

Ok, cool. I'll check the guide on how to do that. Still waiting for the Cobb to arrive so I can't request ATR yet.

[ShaneN.]

why do people run e85 or other mixtures on the stage 2 aggressive tunes? isn't that specifically made for 93 octane? if you're looking at running mixtures or higher octane fuels wouldn't some sort of separate race or custom map be what you'd want to run?