Leaning out the a/f
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Leaning out the a/f
How big of a diff. will it make when i switch the tubing on the maf from 2.5in to 3in diameter piping? Right now my car is running really rich even with the fuel set back as far as i can get it. It mostly just bogs down at w.o.t. then fights through it.
///M
'93 Legacy SS - part out
'93 Legacy SS - part out
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how is part throttle driving? I dunno what your mods are, but you might just have a bad O2. My O2 overheats on the highway sometimes and dies, the ECU thinks it's lean all the time so it richens it up as much as it can. The thing actualy runs better it it decides to throw a MIL and run in limp mode.
If you're talking about putting the AFM electronics in a larger tube, then it's simply a matter of increased calibrated area. A 2.5" tube has an area of 4.9" (Pi*r^2), a 3" tube is 7.06" or a 44% increase in area. Now this doesn't directly relate to a 44% increase in flow, but it's close enough to guess.
If you're talking about putting the AFM electronics in a larger tube, then it's simply a matter of increased calibrated area. A 2.5" tube has an area of 4.9" (Pi*r^2), a 3" tube is 7.06" or a 44% increase in area. Now this doesn't directly relate to a 44% increase in flow, but it's close enough to guess.
- Junior
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I've put a straight thru muffler on mine and noticed a LOT of backfires, mostly at part throttle. I would like to find an efficient way to lean it out just a bit.
But at least too rich ain't too dangerous
But at least too rich ain't too dangerous
92 l swapped to ej22T with 2.0T shortblock
4.111 manual 2.5RS tranny, sti eng mount, wrx I/C, MBC, WRX turboback exhaust, WRX front seats, STI rad cap, WRX specR1 struts, Eibach springs , leg turbo front brake, WRX rear brake.
4.111 manual 2.5RS tranny, sti eng mount, wrx I/C, MBC, WRX turboback exhaust, WRX front seats, STI rad cap, WRX specR1 struts, Eibach springs , leg turbo front brake, WRX rear brake.
Yeh, except you run the risk of fouling the plugs. I know I don't want to pay for another set of NGK Iridium plugs.
It mostly just annoys me. When I was racing that srt 4 a couple days ago, we killed them all the way through second gear. Then hit third gear where it bogged down and they started to catch back up.
It mostly just annoys me. When I was racing that srt 4 a couple days ago, we killed them all the way through second gear. Then hit third gear where it bogged down and they started to catch back up.
///M
'93 Legacy SS - part out
'93 Legacy SS - part out
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What is the accuracy of your fuel tuning software?
Most reduce the injector pulse by .1 millisecond.
Well, every .1ms increase or decrease is a 50% flow increase or decrease. That's why HUGE injectors suck at idling.
If you flow 300cc's of fuel at 1.5ms, at 1.6ms your flowing 450cc's of fuel. And the change from 1.5ms to 1.6ms is something you need to define.
I don't think an SAFC really allows you to work so finely with how and where the jump in injector pulse width happens, does it?
Most reduce the injector pulse by .1 millisecond.
Well, every .1ms increase or decrease is a 50% flow increase or decrease. That's why HUGE injectors suck at idling.
If you flow 300cc's of fuel at 1.5ms, at 1.6ms your flowing 450cc's of fuel. And the change from 1.5ms to 1.6ms is something you need to define.
I don't think an SAFC really allows you to work so finely with how and where the jump in injector pulse width happens, does it?
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2009 Impreza 2.5i Premium. Blue.
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for those of you who have backfires and rich running at part throttle, replace your O2. Unless your injector/pressure combo is grossly different from stock the ECU should be able to compensate in closed loop mode and still run you at a nice 14.7 afr. I run about 42psi Fuel pressure on the stock injectors and it works out great under closed loop, but alows for the fueling I need when the boost comes on. So far I've been lucky, it sticks it right about 12:1 at WOT with no piggy backs. Now that it's cooler I'm going to start turnig up the boost though. We'll see what happend then
- Junior
90L Wagon EJ22E on Toyota CT-26 boost -- Crushed!
95L Wagon on T3/T4 boost :)
www.trdsupra.com [b][url=http://trdsupra.com/library/forsale/]Cheap parts![/url][/b][quote="Imprezive"]alright, I give up, I'm going to NASIOC...[/quote]
90L Wagon EJ22E on Toyota CT-26 boost -- Crushed!
95L Wagon on T3/T4 boost :)
www.trdsupra.com [b][url=http://trdsupra.com/library/forsale/]Cheap parts![/url][/b][quote="Imprezive"]alright, I give up, I'm going to NASIOC...[/quote]
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My O2 sensor is brand new, i replaced it 4 months ago! I'll try some new plugs, maybe colder range.
By the way, i'm running a 2.0l block with 2.2l injectors and ecu. maybe i'm to rich at idle, since it's 10% fuel scheduling at idle. But it idles fine, well... i just don't know
By the way, i'm running a 2.0l block with 2.2l injectors and ecu. maybe i'm to rich at idle, since it's 10% fuel scheduling at idle. But it idles fine, well... i just don't know
92 l swapped to ej22T with 2.0T shortblock
4.111 manual 2.5RS tranny, sti eng mount, wrx I/C, MBC, WRX turboback exhaust, WRX front seats, STI rad cap, WRX specR1 struts, Eibach springs , leg turbo front brake, WRX rear brake.
4.111 manual 2.5RS tranny, sti eng mount, wrx I/C, MBC, WRX turboback exhaust, WRX front seats, STI rad cap, WRX specR1 struts, Eibach springs , leg turbo front brake, WRX rear brake.
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I am running the same setting as your turbo.
But my idle is stay above 1000rpm. and I know the car is running too rich too since everytime when I after start the car, I could smell fuel.
I know my coolant temp. sensor has problem (I put an new one on already) but the car could boost over 16psi without any problem.
If there are any way to lower the A/F ratio it will be a great help.
Ben
But my idle is stay above 1000rpm. and I know the car is running too rich too since everytime when I after start the car, I could smell fuel.
I know my coolant temp. sensor has problem (I put an new one on already) but the car could boost over 16psi without any problem.
If there are any way to lower the A/F ratio it will be a great help.
Ben
92 Legacy turbo with EJ20G engine swap \(^0^)/
Alright, I ran the plastic JEC's MAF for a while and I finally changed it back to the original aluminum MAF from my SS. For the first time since I got the car, the CEL is off. I happened to hook up the charcoal canister and other things but the main thing is, my car really did not like the JEC's sensor being on it.
///M
'93 Legacy SS - part out
'93 Legacy SS - part out
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If it was throwing a code 49, you can trick it into thinking the aluminum sensor is on. This could screw up more stuff than it solves, but Doug's doing it. You ground the blue wire going to the MAF sensor.
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Yeah, grounding the blue wire does work to get the CEL to turn off.
The Jecs MAF reads 4.6 instead of 5 at the same max airflow (for me).
The Jecs MAF reads 4.6 instead of 5 at the same max airflow (for me).
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1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
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1992 Touring wagon, should I keep it?
1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
I'm getting rid of the maf completely next week so it doesn't make too big of a difference to me. However i noticed today that the clutch doesn't like to disengage so I had to drive the car home without a clutch. I think the fork is bent or maybe something wrong with the clutch itself. This sucks cause i spent the day snowboarding and I'm barely able to move now, i know tomorrow is going to be worse and i need the car mobile again by monday.
///M
'93 Legacy SS - part out
'93 Legacy SS - part out
my car runs dead on 14.0 afr at 700rpms idle. thats with 550cc sti injectors not tuned. you guys got to start playing with idle speed control sensor and the screew.
1993 Subaru Legacy 44B STi 4Cam 16Valve Turbo Intercooled AWD
EJ22T, STi EJ207 DOHC, Vi-PEC (Spare Autronic) @ 426.20HP / 394.94ft lb @ 00psi
Tuned By: Franz Diebold ( DIEBOLD AUTOSPORT ) @ NVauto
EJ22T, STi EJ207 DOHC, Vi-PEC (Spare Autronic) @ 426.20HP / 394.94ft lb @ 00psi
Tuned By: Franz Diebold ( DIEBOLD AUTOSPORT ) @ NVauto