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Discussion Starter #101 (Edited)
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).
You might have a bad iac to begin with. Worth a thought.

You can map two different iac tables. One related to throttle opening and the other related to engine rpm. Both are single column tables, labeled as a percentge of opening. I tried a steady increase in the numbers and it just didn't like it. Nice idea, but it just didn't work.

There are more tables available for IAC function. I just couldn't cheat with these.
 

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I noodled with the acceleration enrichment this week. I like the results. Tip in everywhere in the rpm range in a lot quicker. It can launch easy and take off a lot quicker. ITB cars typically need some loving on the accel tables. Throttle roll-on, jabs, and tip-in are all improved. No bogging, loading up, or flat-spots on tip in anywhere in the RPM band.

For those of you doing turbo work, this should greatly help your spool-up. You know how turbos respond pretty instantly on these cars, and this should bring it in even quicker, IMO.
Bumping up something you said a while ago. I'm needing a bit of help with this throttle enrichment. I'm getting a serious lean condition when I jab the throttle. Idle, cruise, WOT are all good otherwise. Any info/suggestions on how to adjust them properly?
 

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Discussion Starter #103
Bumping up something you said a while ago. I'm needing a bit of help with this throttle enrichment. I'm getting a serious lean condition when I jab the throttle. Idle, cruise, WOT are all good otherwise. Any info/suggestions on how to adjust them properly?
Adjust these two tables after recording a few logs. Look for STFT being added during throttle opening events. That's the clue.

Look under the Fuel-Transition tables. Acceleration Enrich and Acceleration Enrich RPM Compensation are two important tables for acceleration enrichment. You can give more tip in fuel based on throttle angle and/or rpm. That's where I got my tip fueling straight.

Acceleration enrich makes broad changes. Moving up the figures there by just a small increment makes a huge change in fuelling. It reads a little weird. The scaling on the columns isn't in perfect order.

The RPM comp table is a bit more straight forward. You can adjust a percentage of fuel added, by RPM. I believe this is a correction table to the Accel-Enrich table. Start here with adjustments.

I was able to dial in the character of the throttle with these tables.
 

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Quick question, will a voltage clamp and RRFPR be unnecessary with this software?

For a 2001 2.5RS, I've been under the impression that a SplitSec Voltage Clamp VC3-100 and 12:1 RRFPR were the traditional items to begin turbocharging on the stock ECU.
 

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yes you can properly scale in larger injectors and map sensors and actually run some boost instead of being a jackass with 5-8psi
 

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Discussion Starter #107
Quick question, will a voltage clamp and RRFPR be unnecessary with this software?

For a 2001 2.5RS, I've been under the impression that a SplitSec Voltage Clamp VC3-100 and 12:1 RRFPR were the traditional items to begin turbocharging on the stock ECU.
They're unnecessary with this software. You can tune more properly with this and dial it in better.

If you ever get curious and have a few hours to burn, mess with the fuel pressure and watch your fuel trims change.
 

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Idk what you whatting? My comment about going through all the work of installing a turbo setup to still have a 14sec car?
 

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I'm RWD with a 4.44 diff with my stock trans. Running 6 psi is FANTASTIC in it. Granted more is nice, but not necessary (due to possibly breaking everything)
 

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Idk what you whatting? My comment about going through all the work of installing a turbo setup to still have a 14sec car?
You're definitely the jack ass here. Not the people who are modifying their cars how they see fit. 5-8psi is plenty of fun over an stock n/a car. Not everyone wants a 10 second car Toretto.
 

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You go through all this effort and work putting some kinda turbo setup in the engine only for it to still be slower than a stock wrx. Good work.
 

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Would anybody here happen to have a data log of a bog standard (or close to) ej251 at start-up or cruising? I have taken a couple of logs of my ecu/engine before attempting to change anything but seem to have some (possibly) strange figures..

1 - my ignition advance is very often LESS then the base (IAM is 1)
2 - my cold start, cranking pulse width was 35.07ms, which seems to be double (17.41ms) the figure in the "cranking base injector pulse width (MT)" figure at 10degC, coolant temp at time of start up was logged at 9degC.

If anyone has an excel datalog I could have a look at that would be awesome! PS I don't mind people looking at my datalogs either if you're interested..
 

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Where is everybody lately? This has gone very quiet!

I've been playing around a little trying to make sure there is plenty of fuel above 5000rpm in my ej251. Have done a few datalogs in very similar conditions (intake temps between 85-113deg F), full throttle in second gear on the same piece of flat road.

Have seen some strange things like the IAM changing from 1 or 0.25 at times, when I have not changed it at all in the ecu. Then also with the injector pulse width times not reaching the same 15.1ms between 2 different logs though nothing looks to have changed!

I installed my 4-1 EL headers which increased the knock retard to a few degrees, tried adding some more fuel but then the IPW dropped to around 14.3-14.8ms from 15.1ms.

I'm wondering if I need to be looking at the Power Mode Target ratios a bit more? Though I may be maxing out the stock injectors (looking into STI pinks and a deatchwerks fuel pump.


BTW now that the 4-1 headers are in I can hopefully get a wideband sensor in soon to double check AFR's more accurately!
 
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