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Flashed Cobb AP Stage 1: Impressions & Overview

3332 Views 15 Replies 12 Participants Last post by  gathermewool
This essay is for my Cobb Stage 1 reflash experience. I did it several days ago in anticipation of more extensive mods.

I had started thinking I just wanted a reflash because I missed how the GD STi seemed to throw you back in your speed and pick up insanely fast in any gear at any speed, something that the peaky, much narrower GR motor's powerband lacked.

Then you know how it goes, you start reading, thinking, researching and I am going to do a more complete upgrade. However, since I will do a stage 1 protune due to its greater safety along with the planned upgrades to an eventual stage 2+ goal, I figured the AP would be a good way to communicate with my tuner regarding engine management issues. I was also curious to try the gains from OTS Stage 1 vs protune to see if the protune truly is a "mid to high 300's hp at the crank" proposition as I had been advised.

So the installation was literally as easy as they said: plug and play. I would say it takes about the same amount of time to scrub down one wheel and make it totally shiny, but the reflash was far less effort, totally sedentary. Just don't open the doors or the process will blotto out your ECU. Keep the doors locked in case anyone might want to open them on you.

As far as the driving experience? Interesting.... interesting.

Initially the car drives wierd. Even after about 80 miles the throttle requires too much input for the reaction and this has been said by others as being common while the ECU is still learning the new tune. Heel toe downshifting and rev matching in the stock tune was one of the easiest I ever experienced in any car I have ever driven; now it's a bit trickier though it has improved somewhat. They say this can be protuned away. It's also hard to drive smoothly at low throttle input at low speed. Maybe this will go away but say you're at 1800rpm in 3rd gear, it's very jerky, and it's not a "fast, eager to go" kind of jerky, it's a very sudden on/off from throttle. This I don't like because stock it was one of the easiest throttles to modulate I have ever tried, I hope it goes away, but in any case, this can be protuned away as well.

It also makes a different noise. While definitely faster, the motor doesn't feel like it's as muscular. There are more higher pitched sounds from the wastegate, more flutter and very little extra turbo whine. It sounds less powerful and more wheezy from a noise point of view even though the power feel is mostly a lot better.

Power wise, it's definitely there; this is the part I (and the reader) was waiting to gloat about. I would say the car feels a little more powerful if you're immediately stepping on it but it still doesn't throw you back in your seat like the old GD's. In terms of throttle response, yes, there is more, the pickup is increased at all RPM's. What really makes the difference is going the distance: not just flooring it but flooring it and keeping the throttle firewalled. When you floor the sucker, it seems to waft forward with torque, and the longer you keep the gas down, the more it rushes forward. Instead of being a more "rev" motor stock with high torque peak, it feels more of a "torque" motor that wafts forward. The urgency is minimal, until you see the speed gauge and the backwards warp streaks of the cars that frantically disapear around you. You don't feel yourself gaining speed, you feel yourself at a speed that is higher than you think you should be, or is comfortable because you did not expect it!

It seems the motor has better low end across the spectrum, biggest difference is around 2500-4000 rpm, but regardless where, this sucker just loves to go, go, go, go gooooo!!!!!!!!. Wife noticed that the car "accelerates a lot more smoothly" and all of the bumps and bruises, hesitations and ups and downs of the torque curve now seem swollen away by a new, testosterone impregnated set of muscular torque curves. I'll repeat it again, it doesn't seem like a big difference initially, but the longer you flex its muscle by staying on the throttle, the more apparent the increased torque and HP feels.

I would say the power difference is subtle until you really get into it and let the car escape. Then its dramatic. 1st gear starts no longer bog or stall easily. Start off gently, and it will get out of the way, quickly, and only with say 1/3 throttle. Man, that's what I'm talking about!

2nd and 3rd gear pull very frenetically, much to the wife's chagrin. Now she feels thrown in the back of her seat and I see the effect (but I still don't feel thrown back).

Beyond that I would say downshifting is not needed. If you are in 5th, I would say even 6th on the highway, within a few car lengths you are streaking away at warp speed. Apply full throttle at any speed on the highway and it seems like all of a sudden you're not the one flooring it; it seems like the other cars shifted into reverse and they are flooring it at full bore away from you.

Overall I would rate the power difference as one gear lower, which is great. Once you're in the higher gears, you get the acceleration of one gear less, but in a taller gear that lasts longer. This is particularly awesome in 5th and 6th which used to not feel very good.

Another upside (or downside) of the power is that now the car is a little scary to drive. There simply isn't enough room on the highway unless it's clear because you will be going 65-95 in literally just a few heartbeats, and it keeps going. The rears of other cars loom on you quickly, but at times you feel the car shake its tail under power, more in the lower gears. There is also much more useable power oversteer in tight curves in the lower to mid gears. But overall now the car feels like it may need slightly taller lower gears and a little stiffer chassis and suspension, which is of course pending the protune. But the fact that now the car seems a tad overpowered is very telling of the power gains. Even though it doesn't feel as urgent and frenetic as a GD, I would venture to say that next to each other, particularly in the higher gears and past 100mph the GR Stage 1 Cobb OTS 93 octane map might just edge out a GR and, at least subjectively, be on par with a 335. Maybe I had better results than most; for me the longer I stay on the gas the faster it feels; just a stab of the throttle not so much, but boy, those highway pulls certainly rival a G37x, and that's saying something.

In other words, the motto of first chassis, then suspension, then tires, then brakes, lastly power is the best way to go. Cobb Stage 1 93 Octane for the GR STi's definitely is the testosterone shot in the arm the car needs. If it weren't for the potential knock issues, the car should have come this wayIMHO Cobb AP Stage 1 is pretty good, but problems can still exist. I think it's a nice jumping off point to a full stage 1 protune, but alone I'd be worried about knock, especially running a 93 octane map (which I am). The Cobb AP just makes sense if you're modding. Only real downside are warranty issues, but once the modding bug sinks its teeth in you.....

I still recommend a full protune which is cheaper and gives more power, but this is a nice intermediate step and the AP (even V2) is a good tool regardless.
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That has to be the most extensive stage one reflash post ever. lol

Glad you did it and are enjoying it though!
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"testosterone impregnated set of muscular torque curves" haha!

nice write up. I forgot what a stock STi drives like but I recall my GR being just as quick as my GD and neither would be slower than a G37 on the highway. These cars all will trap about the same.

tuned STis are simply Much more fun than stock
If you think the OTS map is good you really should look into getting professionally tuned.
Getting ready to take the steps myself...

Debating my own course of action as my AP arrives on Thursday.

Thikning about flashing to Stage 0, logging for a few days at Stage 0.

Then, I'll either flashing to OTSStage 1, logging again and adjust octane and/or wastegate or maybe just going straight to a protune (have the tuner lined up, just have to have my AP in hand so he can save the tune to it and schedule).

Tempted to do the OTS first just to convince myself of said value of protune after the fact.
You may want to log and post that up. You shouldn't be experiencing too much jerkiness.
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You may want to log and post that up. You shouldn't be experiencing too much jerkiness.
It's going away thankfully. Most of the negatives in term of feel are getting better as the ECU is learning.

For example when I started it, and it was fairly warm oustide, it idled at 1800 rpm and the throttle control was sketchy for about 10 seconds.

The more it drives around, the better it feels.

But I am not going to bother datalogging because the ECU has not learned yet (IE I have not driven 200 mi with the reflash), it keeps feeling better, and by the time I do the "recommended 200 miles" I will have it already protuned.

Your Stage 1 story with the complication around 10k miles was not missed to me, but I just wanted to see how the OTS map was like, I hear protune is a lot better (and safer due to being knock free).

But about 200mi after the protune, I will still definitely datalog
I would not count on 'protune' being knock-free. It's better than OTS map because it's done somewhat to your specific hardware, but it's not tested in all weather/load/gear conditions. You should still log the crap out of it and keep an eye on knock. Personally, I'd add an extra layer of safety on any tune, "pro" or not. That is, for example, get it tuned for 91 and run 93.
I would not count on 'protune' being knock-free. It's better than OTS map because it's done somewhat to your specific hardware, but it's not tested in all weather/load/gear conditions. You should still log the crap out of it and keep an eye on knock. Personally, I'd add an extra layer of safety on any tune, "pro" or not. That is, for example, get it tuned for 91 and run 93.
This is the most important piece of information on this thread. Whenever you are modifying your car, constant watching is crucial to the health of your car. Pro tuning can only be as good as how long your tuner has been working with you. A well tuned car should do good for most of the year, however, it is crucial to get a lot of data over the FULL range of temperatures that the car can see! Which takes time. No tuner can guess how to setup compensation tables based on where you live! It takes DATA. Which of course takes time for the car to see said range of temperatures / humidity / elevation changes!
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Moved to the appropriate technical section.
I received my v3 on monday, installed it and my SF intake, and haven't had an issue yet. My initial data log showed a low end knock when i hit WOT, but learned it away quick, and I haven't seen it again since. I set one of the gauges up for the knock so if it does come up when driving I can see it and then data log after to check if it's still there or learned away. I may be getting a protune in the near future though so I'm not too worried. For now though my car seems to like the OTS stage 1 93 map from Cobb, and I love it back very much!!
This is the most important piece of information on this thread. Whenever you are modifying your car, constant watching is crucial to the health of your car. Pro tuning can only be as good as how long your tuner has been working with you. A well tuned car should do good for most of the year, however, it is crucial to get a lot of data over the FULL range of temperatures that the car can see! Which takes time. No tuner can guess how to setup compensation tables based on where you live! It takes DATA. Which of course takes time for the car to see said range of temperatures / humidity / elevation changes!
Thanks, I've been keeping this in mind as well but from what I have read one should give it the full 200 miles before a datalog as you can get false positives until it "learns". I'm not going to bother datalogging until I have 200 miles.

This is good advice though, at altitude, temp/humidity changes etc. I figure I'll probably datalog about once a month or so indefinitely *or* at every major change in atmospheric condition
this man should write STI novels, jesus haha.

Its fun hearing how we can unlock our cars. I am still a virgin and haven't yet, I think the V3 may seduce me into it
Your AP will show you pertinent information right away and after a change is the most important time! Your looking for excessive knock, not occasional false knock. Why have 200 miles of blinders. 200 mi is plenty of time to loose a ringland.
Thanks, I've been keeping this in mind as well but from what I have read one should give it the full 200 miles before a datalog as you can get false positives until it "learns". I'm not going to bother datalogging until I have 200 miles.

This is good advice though, at altitude, temp/humidity changes etc. I figure I'll probably datalog about once a month or so indefinitely *or* at every major change in atmospheric condition
100% disagree!

The first thing you should do after reflashing or modding and reflashing, is log, log, log. The data may not be normalized, but the most important data point to note will be whether the tune is safe. The chances of going from good to dangerous with an OTS map and the correct mods for the map are slim, but that's besides the point. Logging immediately is simple and effective.
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