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Old 11-14-2019, 11:08 AM   #26
F1EA
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What Nick said ^

It's not that the Stage 1 OTS is "harmful", it's mostly that it's not very useful and for sure not worth ruining your warranty for.

Also, the stock tune is pretty smooth and driveable. No use tinkering with it, much less for an OTS 1.
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Last edited by F1EA; 11-14-2019 at 12:29 PM.
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Old 11-14-2019, 01:02 PM   #27
vlad11591
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I can't stand the stock tune in daily driving unless it's an intelligent mode. But then you're getting passed on the highway by a Kia sport, with better interior than your car

I was really just getting at I wouldn't do anything aftermarket, aside from a cat back, without doing a custom tune. I just can't get down with intake/downpipe going stage 2 on an OTS tune.

I wouldn't go pro tune for stage 1 either. You have a lot less risk getting denied for a warranty for an OTS tune if they pull your ECU rather a dyno tune since it's only one ECU reset/keyturn.

I'm pretty happy with it as it sits on the OTS tune. Plenty of power for some fun.
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Old 11-14-2019, 03:07 PM   #28
F1EA
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Quote:
Originally Posted by vlad11591 View Post
I can't stand the stock tune in daily driving unless it's an intelligent mode. But then you're getting passed on the highway by a Kia sport, with better interior than your car

I was really just getting at I wouldn't do anything aftermarket, aside from a cat back, without doing a custom tune. I just can't get down with intake/downpipe going stage 2 on an OTS tune.

I wouldn't go pro tune for stage 1 either. You have a lot less risk getting denied for a warranty for an OTS tune if they pull your ECU rather a dyno tune since it's only one ECU reset/keyturn.

I'm pretty happy with it as it sits on the OTS tune. Plenty of power for some fun.
Cobb doesn't do Stage 2 OTS with a Intake/downpipe. It is downpipe ONLY.
OTS Stage 1 is available for stock or with a Cobb intake.

(a catback is considered stock for all cases)

Also, I don't think the ECU reset/keyturn works as you think it does. It records the keyturn cycles on your current tune, regardless of whether it was custom or OTS. So the key cycles will show up the same if you reflash to stock. Subaru has absolutely no distinction for warranty whether it's a custom or OTS tune (ie. they allow for neither).

From what you said, what you want is a OTS Stage 1.

I find it makes the car worse, on top of x'ing your warranty. But if you don't like how it drives stock, then a OTS 1 is as basic as you can get. There is more freedom for which parts and fuel to tune for if you want a Stage 1 custom tune, as well as a bit more options to tune for improved driveability.
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Old 11-14-2019, 03:27 PM   #29
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Sorry, Cobb Stage 1+ includes the intake, not stage 2.

Also, when you're doing multiple revisions on a dyno tune, you're resetting the ECU/PCM. So on a custom/e tune, you can have about 10-20 revisions, before the final tune. If any warranty work, and the dealership wants to look at your ECU they will see all those resets and altered PCM tables.

You know how many resets on an OTS tune? 1

Why do you feel the OTS makes it worse? I guess it's really what your goals are for the car, but I've used MAP Stg 1 and Cobb and great improved drivability on both WRX and STI.
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Old 11-14-2019, 04:50 PM   #30
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Quote:
Originally Posted by vlad11591 View Post
Sorry, Cobb Stage 1+ includes the intake, not stage 2.

Also, when you're doing multiple revisions on a dyno tune, you're resetting the ECU/PCM. So on a custom/e tune, you can have about 10-20 revisions, before the final tune. If any warranty work, and the dealership wants to look at your ECU they will see all those resets and altered PCM tables.

You know how many resets on an OTS tune? 1

Why do you feel the OTS makes it worse? I guess it's really what your goals are for the car, but I've used MAP Stg 1 and Cobb and great improved drivability on both WRX and STI.
Yeah fewer flashes on the OTS. But from what I understand, the ECU does not store the number of flashes; only the number of key cycles on the current tune. This is a *or so I've heard* thing, so not 100%....

And agree. OTS is more "safe". You are subject to fewer errors, mistakes, issues during flashing, etc. By the time you get an OTS, they will have had quite a bit of QC done to your specific tune, with multiple cars and multiple conditions... so I do trust it (all my logs were great - so AP went to the glove box).

With Stage 1... the problem (with Cobb OTS 1) is that it kills the throttle mapping effect between i, S and S# and instead substitutes for a slightly different boost target for each mode. All while only adding negligible extra power. I felt more power gain from a K&N drop-in and catback on a WRX than from the OTS1 on the '19 STI.

Since you have a MAP tune, then maybe that is better than Cobb's. I wouldn't doubt it, but also, I would say it is more aggressive/less conervative than Cobb's. Also, the OTS are a good improvement on driveability for the WRX; but not so much for the STI... mostly, because to me, the stock '19 tune is already really good.

OTS Stage 2 it's a whole different thing. The downpipe significantly increases boost response. So you get a lot of early torque, higher target boost and a better top end. Stock tune was pretty linear and smooth... the Stage 2 is still linear but with noticeably more early torque, and you do notice the peak boost hit because the turbo spools faster. Also, you can definitely feel a difference between i, S and S#. It is not as noticeable as stock, but much better than OTS1. So it kind of offers the best of both worlds... linear throttle, good low torque and the old-school turbo kick. And when you think about it... it's just the cost of a downpipe (plus AP of course).

The downside is that with a full Cobb turbo back it is pretty loud, and still... not that fast. So people will think that you're racing even when you're not.

Another downside is that you do get to feel the 2800rpm stumble every once in a while... this rarely happens, and only under low throttle/load conditions so it's more an occasional nuisance than a real problem...

Last edited by F1EA; 11-15-2019 at 02:47 PM.
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Old 11-20-2019, 08:18 AM   #31
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Coming from cobbs ots stage 1 and a custom e-tune for my car, to anyone that claims they can squeeze out more power than cobbs ots map, is a fact. I had better throttle response and it was faster both eith my butt dyno and using cobbs 0-60, don't really remember the numbers well, I'd redo the runs but I have gone to stage 2, about to go stage "2+" as I'm about to install an ewg set up with an ebcs.

I would say if you want to feel the power, a stage 1 e-tune with just a catback at 18-19lbs (low 20s, 19.7-19.8) feels amazing and is definitely way better than cobbs ots. A lot less knock too, and a lot more fuel efficient, about 1 mpg difference between cobbs and 1.5 over stock.
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Old 04-08-2021, 12:11 AM   #32
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'19 STI OEM vs COBB Stage 1 (ACN91) vs MAPerformance Stage 1 (91)
Same day, same tank of fuel (California ACN91).



I did 5 pulls with the MAPerformance tune hoping that at least one of them would be better.. but the one above was the best.. Maybe their 93 octane tune is better I've heard great things about their FA20DIT E30 maps.

Yes, the OEM tune made more power from ~5800+ RPM even on repeated pulls. COBB's ACN91 tune is very conservative (richer AFR & less ignition timing) in that region. The extra torque down low and the higher redline more than make up for the slight power loss up top. Especially considering the COBB OTS tune is free and the MAPerformance tune was ~$75. The higher redline allowed me to reach 60mph in 2nd gear dropping my 0-60mph time from 5.46 to 4.85 seconds by eliminating the shift to 3rd (I know, it's a pointless marketing/bench racing metric).

The OEM torque curve is nice and flat creating a linear powerband. The tuning on the '18 RA & 19+ STI is really good. You lose a lot of the throttle response/mapping from both the COBB & MAP OTS tunes (especially in S#). This is personal preference though as some people prefer to always have a very linear throttle map.

I'm working on my own custom tune now and can post the results for anyone interested. I've definitely found some extra power over COBB's OTS map even on ACN91. I've also retained the OEM throttle response for the various drive modes as a nice gimmick.

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