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I'm using the dragy performance meter. It's been tested at the drag strip to be accurate within a few hundredths of a second. The key to getting a good time is abusing the drivetrain to get a decent launch. I've also been using it to measure my 5-60 mph time (no launch) which is around 6.1 seconds.
I'm glad too see your getting a 5-60 mph time better than the 7.0 seconds that R&T got. What RPM are you launching to get your 0-60 time?
 

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I've been launching between 4500-5000 RPM with consistent times in the 5.5-5.7 second range. I think there's a bit of room for improvement, but definitely not getting a sub-5 second time with the stock redline.
I'm very interested in your build and I want to thank you for posting everything your doing up on the forum. In the age of Instagram and FB, we need more in-depth content/discussions.

I'm really interested to see how your upgrades change your real world performance. We always gauge performance upgrades with dyno results, but to me, I can't comprehend how that equates to real world driving performance.

I'd love to see some testing where auto journalist take a New stock STI and compares it's numbers against something like a Cobb Stage 3 w/OTS tune (as this is something, in theory, that should repeatable vs a customized tune).
 

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The COBB stage 1 tune significantly dropped my 0-60mph time by eliminating the shift to 3rd (5.65 -> 4.85 seconds). Of course, if you guy by the magazine/media outlet standards (1 foot rollout), that time drops to ~4.65 seconds.

COBB Stage 1:
0-60mph: 4.85 sec
0-60mph (1ft rollout): 4.65 sec - this is the standard for performance testing
This is not bad for the COBB Stage 1, much better than I'd imagine. Thanks for doing the testing and writing this up!
 

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Nick,

I think those numbers are great for a mechanically stock STI. I would say perfect for a street car. I'm glad your posting this data because I have a hard time relating how changes to a stock platform relates to a real world driving experience. For example, "My STI put down 330 WHP and 350lbs of TQ", I can't relate that to anything but other peoples dyno numbers, but I can relate changes to 0-60 times.

I'd love to see one of these big box automotive media outlets or even a vendor (like Cobb) take a stock STI and run it against a modified STI at the different "stages" and capture the type of data your capturing.
 

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Thanks! It just goes to show how capable the STI still is with light modifications. Granted, I spent countless hours on this tune :LOL:

My 5-60 mph has also improved quite a bit:

Stock: 6.01
COBB Stage 1: 5.73
My tune: 5.16

Having a downpipe (stage 2) would help improve this metric as the main enemy here is turbo lag.
That's a great improvement in 5-60, did you. think a DP would get it under 5s?

Do you tune for living or is this just a hobby?
 

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Just a hobby. I've always loved modifying and tuning cars.. and understanding all of the engineering behind it. I have my COBB tuning certification and went through all of HPA's courses. I had planned to start my own Subaru tuning business, but all of the recent EPA crackdowns, fines and now CARB testing for any non-CARB approved tune during smog just made it not worth it. The EPA & CARB are really trying to put an end to aftermarket performance tuning for ICE engines. There's a lot of risk being a tuner now and I'm not sure how much longer it will be a lucrative endeavor, especially given the cost of COBB's protuner license. EVs are sadly the future.

I think a downpipe could definitely get it under 5 seconds.
Very cool that you got certified and took all the courses! I do fear for the future of our hobby, although I've come to terms with our EV future and hopefully in the future, classic ICE vehicles will be something that "enthusiasts" can still enjoy on the streets.

All of this has made me rethink modifications and it seems the safe bet to avoid any CARB issues is just doing a Cobb Stage 1, as it is 50 state CARB legal. I'm content with my stock performance and per your numbers, stage 1 is more than enough for my street car. I also have 93, so I wonder how that would effect your results.
 

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On 93 you should be very close to my numbers or slightly better in some areas. I spent a lot of time balancing the AFR, boost & ignition timing in the areas where I was knock limited trying to make as much power as I could safely. If I had access to 93, I could probably squeeze a bit more power out over COBB's map, but it's honestly really good for essentially being free with the AP. Any honest protuner will tell you this. There's very little power to be gained from a stage 1 "pro" tune. However, there are gains to be had in other areas as it's tailored to your car and your fuel, climate, altitude, etc.

Compared to COBB's OTS, I spent a lot of time in the following areas:
  • Leaning out the AFRs at WOT and especially in the cruise areas to improve fuel economy. COBB's maps are conservative and run quite rich.
  • Fine tuning the target boost to minimize boost error, integral & proportional gains to prevent boost spikes/overboost as you reach peak boost between 3-4k rpm.
  • Smoothing out the ignition curve to improve driveability and reduce knock.
  • Changing the throttle mapping. I retained more of a stock-like throttle mapping with the drive modes (I, S, S#) as I wasn't a fan of the single linear response in all of the drive modes. Of course, the drive modes still control the amount of boost that is available.
Carrying power to 7k rpm on ACN91 was quite difficult due to knock and the turbo running out of steam at that point. The VF48 physically couldn't make any more boost up top (with stock hardware), so it was all about balancing timing & AFRs without encountering knock due to the crappy fuel that we have in California.

It was a really great learning experience and quite satisfying. You understand what the "pro" tuners are doing and can go above and beyond since it's your personal car and you have the time and passion. I really can't recommend HPA's courses enough for the price. They really establish a great foundational knowledge. They also have worked examples for tuning the EJ & FA and spend a lot of time on understanding Subaru's knock control system.
Sounds like you really got your tune dialed in and it's very cool that your able to tune your own car as an enthusiast. I liked that your retained the stock-like throttle mapping as that's one area that I'm hesitant with the Cobb OTS, as I'm not sure I'll like the targeted boost and linear throttle vs the stock configuration. Does the stock (I, S, and S#) modes alter boost or any other settings in anyway or is it purely just a change in Throttle response?
 

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Great information and thanks! I've read many times that the different modes only effect throttle response, so thanks for clarifying. I'm going to study the tables you posted and try to figure them out.
 

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The only problem is that it requires a perfect, near redline, clutch dump for the launch...
Ouch! But Great results! More than quick enough for a street car and still fun, engaging to drive, and requires some level of skill. Telsa's and all these recent quick, but non-engaging cars that require little driver interaction are of little interest to me.
 
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