for those who have installed gm 2, 3 or any other MAP sensors, have you had to adjust your "Atmospheric Pressure Bias" table??
I just tried my bosch 4 bar map sensor and adjusted the VE table so the columns start at 40kpa (bit higher than the stock 20kpa but this is the minimum figure that map sensor reads), up to 180kpa as I wont be boosting my car above that!
Then I adjusted my VE table to still match the stock table from 20 to 100kpa (though the number of columns has greatly reduced). Installed the sensor and started the car from cold. It started and the revs bounced a lot, when I levelled out it idled ok but I highly doubt the car was driveable. If I jabbed the throttle it would almost stall afterwards and the revs would bounce around a lot..
THEN I realised that I didn't adjust he atmospheric bias table (and also any spark tables). The Bias table columns had changed to match the VE table (40kpa up to 180kpa), but the actual table figures had not moved accordingly. Ie. the VE figure in the 100kpa column of the bias table was now sitting in the 180kpa column, for that particular rpm. So I'm guessing that this may have had a hand in the rough running..
I'll try to re-adjust the atmosph. bias table and try again, but am still interested in other peoples results. Cheers!
EDIT: Here are some before and after figures of the stock vs 4bar. I tried to do these as close as possible to eachother so the engine didn't warm up too much and make the comparison a bit off:
I re-did all the maps which were kPa based and it still ran like a pig. I was able to compare a lot of figures (stock vs 4bar map) at idle for coolant and intake temps which were very close.
The stock map sensor reads 32kPa at approx. 825RPM, inj. pulse width = 3.0 - 3.3, ign advance = 7-10deg.
The 4Bar map sensor reads 44kPa at approx. 850RPM, inj. pulse width = 3.6, ign advance = 2deg
Conclusion: The ecu does not like this map sensor which is a 50-400kpa sensor. I have ordered a 20-300kpa sensor, hopefully it idles (and then drives!) much better.
Last edited by crjohnson; 02-27-2018 at 09:25 PM..
Well I ordered and trialled the 20-300kpa bosch sensor. Remapped the VE and timing tables for 20-180kpa, only issue I ran into was the offset and slope values. I calculated a negative offset value of -6.35 and the software wont let me enter it!
So I tried it at 0 offset anyway to see if the engine would idle nicer than the 4bar sensor. It did, but the kpa figure in the datalogs looks to be out by 6kpa.. The voltage figure logged calculates (in excel) to an accurate kpa figure but I was worried about the effects on the timing tables etc so I pulled it out and stuck with the stock map sensors
If the ecu is calculating an incorrect kpa I need to fix that somehow!
Last edited by crjohnson; 03-05-2018 at 02:08 AM..
I've got another new IAC on the way. The idle relearn function seems to make them fussy after I enable the function and then disable it. I get codes for both high and low voltage at the same time.
Still not able to raise the redline effectively, either. In gear, it will rev to the new limit once, like clockwork. In gear with the clutch in, it hits it every time. Clutch out in neutral, it hits it every time. In gear, I get it exactly once
Hi guys, I am still edging closer to the 550cc injector install but am a little worried about the fuel accel. enrich (or tip-in?). I don't have access to the Fuel Transition settings with my 2002 ADM outback.
Does anyone here have experience putting larger injectors in and having to change any enrich settings?
So far I have updated a new ECU map with new Load and Airflow scalers, offset and slope figures for the new injectors, multiplied the cranking pulse width by 0.509 (280cc/550cc). Hopefully that is going to be a fairly good start to get it running. I did notice on a recent log, -20% LTFT at idle which might need some attention first??
Edit: just had a thought that the delta 1500 cams could be the cause of the high LTFT's at idle?
Last edited by crjohnson; 04-16-2018 at 05:39 AM..
Turn down your VE settings near idle on the main VE table, first. It does have less VE at idle, so you aren't lying to the ECU. This is where the use of strategy comes into play for making your maps. I pull 32kpa at idle. I bet you see around 25ish.
Maybe try fiddling with the injector end angle table, say 210deg moved up to 220-225deg. Later injection timing is used on bigger cams to smooth out the idle with HP tuners if you had a bigger cam on an LS. It might make your LTFT issue worse at idle, maybe. It can make the tip in throttle a little sluggish at idle, too.
Idle speed target may need a slight nudge upward, too. IAC programming can be a little tricky. I spent a lot of time there to dial in idle on my twin throttles.
Last edited by ImprezaRSC; 04-18-2018 at 02:47 PM..