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2001 Impreza 2.5RS+T 2001 Legacy GT
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Your wideband does not output a signal that the factory ECU can translate. The wideband 0-5v output is for piggy backs and standalones.
 

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2001 Impreza 2.5RS+T 2001 Legacy GT
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What is your BSFC ??? I don't think that should be possible. Not on Earth anyway!
 

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The subaru of many acronyms
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The rear o2 can take the 0-5v input and log it, but I believe you lose a lot of resolution in the ecu since it only logs tenths of volts not hundredths.
 

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100% duty cycle on 440s with e85 is a little over 250 crank soo not that big of a deal. Still probably under 200 wheel hp.
 

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2001 Impreza 2.5RS+T 2001 Legacy GT
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I got two websites that show 230 crank, and one showing 258. And that's being on the safe side of 90% DC. TIL you can still max out big injectors NA.

The ECU expects 0-0.9v from the rear O2, not 0-5. The ECU only sees three things from our O2 sensors. "Right" "wrong low" and "wrong high" and it adjusts accordingly.
 

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2002 Subaru Impreza
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So I'm just getting started tuning my 2.0N/A. I read that around 12.5-13:1 AFR is best for torque, so I was thinking about playing with the power-fueling map. Is it okay to make widespread changes to the map? What do your maps look like? I guess I'm a little scared to make big changes haha.
Thanks for the help.
 

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I'm sorry, but could you clarify?

I should be buying this over the summer, and want to play with it before I go back to work, so I've been reading as much as I possibly can.
 

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2000 2.5RS BRP
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Discussion Starter #93 (Edited)
https://www.enginebasics.com/EFI Tuning/Closed Loop o2.html

Basically, the car warms up in open loop until a preset temperature. The ECU doesn't refer to the o2 sensor for feedback. This typically occurs over 4500rpm on our stock ECUs and during warmup. You can adjust the rpm and load points where it switches from closed loop to open loop. This just keeps it in open loop all the time.

Bump that warmup temperature setting beyond where the engine operates, and the ECU always operates in open loop. It's a dumber mode where it just outputs, basically. It'll read throttle position and basic inputs, but doesn't adjust for cruise or lean out to stoich. It stays in power mode everywhere.
 

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If it doesn't lean out to stoich, that means that the exhaust is less clean... but are there any other drawbacks to keeping it in open loop?

ImprezaRSC, thank you so much. This will be an interesting summer.
 

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Keeping it it in open loop means it will never trim fuel, so fuel mileage will suffer.
 

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Discussion Starter #97
It's more of a race map thing. I'm seeing what kinds of dirty tricks it will let me get away with. This is one. I wouldn't do it daily on the street or for long highway trips.
 

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It's essentially the same thing as unplugging your O2 sensor, but no check engine light. Lets you target the AFR you want to, without "factory settings" interference basically.
 

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Discussion Starter #99 (Edited)
Anyone else using the AH966X-MT template? This template is the basis for my latest exploits.

I'm going to ramble a little bit here, as I'm still hammering out a good strategy and some little issues here and there.

What I'm trying to roll together is my street map that gets good mileage, and "goon mode". I just shove it into open loop by 47kPa over 2800rpm at 0% throttle, so it's in open loop all the time over 3k. Putting that low end hit from open loop into my street map is what I'm working on.

Cruising around 2500rpm up to 5th gear shouldn't bog uphill. The challenge for my specific combo has been getting getting it to accelerate uphill without a bog and just tipping the throttle in a little to get there. Without AVCS being active, this is a bit of a challenge with no cam overlap. I'm basically getting around it with "good footwork" in the mapping. Transitional fueling wasn't the only tool. The VE-throttle comp table has become useful with tuning out that bog at low rpm in higher gear at light throttle.

Rolling into the throttle always left a little to be desired on this combo. It's the last missing piece that I was trying to address. I can finally keep it in 5th gear around 2500rpm on winding roads and it won't fade or drown going up a steep hill. A turbo car doesn't really have this problem. It just uses a little boost to get up the hill. A 2.5 has a lot more torque available. This is a round peg in a square hole with a smaller 2.0L with no AVCS. I made that round peg fit in that square hole :).

The injectors just won't give up any more than about 6600rpm comfortably. I have to accept it. They're just done up there. E85 would stutter a bit at 5800-6k. On gas, it is done a little past that. They just won't cough up 100% IDC on the top end. I've held onto them for 10+ years. They've done their duty, pun intended :p.

Where I was cheating with the IAC sort of worked by holding it wide open. I closed it back down a little and gained some more IDC on the top end. It was worth a couple hundred rpm, but not much.

I had also tried to map the IAC, but it made the throttle a little jerky. Best to just open it and keep it open at a set level. Working the VE throttle comp table is a better option to tailoring fuel delivery instead of trying to tweak the airflow. I've got two throttles and was just being greedy with giving it even more air. The action of the valve opening and closing disturbs the airflow too much. You can open it a fair bit and leave it there, but you can't give it any gradient mapping and gain anything. I'll leave mine between 35-45%. Best to just open it early and keep it there.

I'll have to make a list of things that didn't work and what they did. I never had any catastrophies, but paid attention to what worked and didn't work. The difficulty is not leading you down the path of my build. It's an n/a car with n/a problems.

That's all for now.
 

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ImprezaRSC what changes did you actually make to the IAC to make it jerky?

I have an aussie 2003 Outback (ej251, manual) that has terrible on/off throttle jerk and I was hoping to try fix it a bit with the bluessm (just waiting for the ecu to be made compatible and I should be right to go i a couple of days).
 
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