OAR deviation concern

jbailer said:

You're very possibly correct. I'm going by experiences people have shared in the past. The general consensus from early development was if you got an O/R DP, it was significant enough to require a tune to compensate but if it had a cat at all, even high flow, a tune wasn't needed. I can't say for sure because i haven't experienced it. The DP would be the only component that would require a tune, if that...

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The factory tune is pretty conservative with a lot of nannies in place to deal with abnormal conditions that occur which are out of range for what it is supposed to see. Throttle closures are one of the primary strategies the ECU uses to control boost. If boost ramps up very quickly because of aftermarket parts, the overshoot may happen before the ECU can intervene and close the throttle. This could explain the boost oscillations the OP is experiencing.

You can get away with putting air intakes, a cat back exhaust, the DV+, and plugs without tuning for it, but this is not ideal. One step colder plugs are even a little questionable. The stock heat range plugs work well on the factory tune because boost is conservative. I think anything beyond that, you need a tune that has been adjusted to compensate for the additional parts. This is where the colder plugs also come into play.

TEXAS HEAT said:

The factory tune is pretty conservative with a lot of nannies in place to deal with abnormal conditions that occur which are out of range for what it is supposed to see. Throttle closures are one of the primary strategies the ECU uses to control boost. If boost ramps up very quickly because of aftermarket parts, the overshoot may happen before the ECU can intervene and close the throttle. This could explain the boost oscillations the OP is experiencing.

You can get away with putting air intakes, a cat back exhaust, the DV+, and plugs without tuning for it, but this is not ideal. One step colder plugs are even a little questionable. The stock heat range plugs work well on the factory tune because boost is conservative. I think anything beyond that, you need a tune that has been adjusted to compensate for the additional parts. This is where the colder plugs also come into play.

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Good point, agreed. If that's the case, it really shows how effective the high flow cat and DP are that it's making that much of an impact. I'm not saying that's good or bad, just how much it's impacted the flow rate. Like everything, it needs to be accounted for in the tuning whether that's done through the nannies in the tune (elasticity) or adjusting the parameters so it's working normally. In this case logging the throttle position PID that was used is good as it tells part of the story. As long as you know that the pull was done WOT.

I haven't noticed any issues with the stock tune and OR downpipe, CAI, DVCC and ETS intercooler.

How close are you monitoring the boost during WOT pulls?

Marvinmadman said:

I haven't noticed any issues with the stock tune and OR downpipe, CAI, DVCC and ETS intercooler.

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I think what's triggering the nannies is the torque peak hitting like a train when going WOT overspinning the turbo in the lower RPM range. If I ease into the throttle the ECU doesn't cut the boost.

jbailer said:

Good point, agreed. If that's the case, it really shows how effective the high flow cat and DP are that it's making that much of an impact. I'm not saying that's good or bad, just how much it's impacted the flow rate. Like everything, it needs to be accounted for in the tuning whether that's done through the nannies in the tune (elasticity) or adjusting the parameters so it's working normally. In this case logging the throttle position PID that was used is good as it tells part of the story. As long as you know that the pull was done WOT.

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Haven't really needed to watch it that close, but I see 22 or so at times.

To effectively analyze this information, you really need multiple samples per second. Anyone have a good logging mechanism to do that? Like I said, the Cobb AP is great for it so I know the OBD2 in the car is very capable of delivering the info but the OBD2 solutions that I've experimented with are only offering about 11 PIDs/second while talking to the app manufacturers, they claim I should be able to get up to 40-60 PIDs/second. I'm using an iPhone which uses Bluetooth LE which may be limiting the throughput. The phone matters too, I'm using an iPhone 6+. I've heard from one of the app manufacturers that the iPhone 6S performed better than the iPhone 7 in their testing.

If I have to buy a used Android phone or tablet for logging, I'd do it but not until I knew it would be a good solution. I'd even consider some other datalogger. On my 2006 GT I used a LM-1 from Innovate with a LMA-3 auxiliary box for sensors collecting directly from the sensors themselves but I'd like to believe that I could find an OBD2 solution that could deliver sufficient performance and that is validated by the Cobb AP.

I'll get a good log very soon with my X4 and laptop along with Torrie's config file.

Marvinmadman said:

I'll get a good log very soon with my X4 and laptop along with Torrie's config file.

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I didn't think about SCT. I used to use that for logging when it was my tuning device on my last Mustang. It also provides very good performance. I wonder if you can use that without loading it to your car, just use it for monitoring?

Sure can. That's how I'm using it

My car dyno'd 370 calculated crank hp with torrie's 93 octane tune. It was a beast in 4th gear, but I didn't feel safe using it, and didn't want to mess with having to alternate between a summer and a winter tune so I switched.

Marvinmadman said:

I'll get a good log very soon with my X4 and laptop along with Torrie's config file.

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He said he can build me a singular tune to not have to switch back and forth.

Good to know

Marvinmadman said:

He said he can build me a singular tune to not have to switch back and forth.

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Yep. I have a different issue that ill be posting a thread about. Really light throttle and I see a bunch of "knock".

In the logs?