What AFR should I be running on deceleration. It decels at 12.5 or so and then at around 1k it pops over to lean about 15.2 then at idle settled at 14.7. But I get a little popping out the exhaust. Not loud or anything, just a burble kind of noise but with a very slight pop. Just thinking on decel running on the rich side is causing it. What is the consensus.
1999 Corvette Coupe Stock Block. Vortech Si Supercharged, Siemens 60# Injectors, High flow FP, X-Pipe, Catback.
2005 Dodge Magnum 5.7 Stock except CAI
Your short pulse tables need work, sounds like your minimum pulse width is too high.
Can you please explain default pulse width theory? I have a lean decel and can't figure out the issue.
There is no theory, it is called properly tuning injectors. The bigger the injectors the lower the pulse widths will be at low RPM/MAP, which means the stock limits may be causing the injectors to not go low enough. There is a lot that plays in to this with new injectors: short pulse, short pulse adder, offset and transient. If they are all setup correctly, then it is more than likely an issue in the fueling calibration.
Sulski Performance Tuning
2000 WS6 M6 - LS6 (long block, refreshed top end), 10.8:1 CR, 90 mm ported FAST, Exo-Skel, 227/232 cam, QTP HVMC, EWP, GMMG, 9" w/4.11s
2018 Sierra SLT 5.3L A8 - Airaid intake tube, GM Borla catback, L86 Intake/Ported TB
I have the proper data but afr goes lean when I decelerate.
Going lean on Decel is okay. If you have DFCO it goes even leaner as it pretty much turns off the injectors. Its the 12.5AFR I would tackle, that is too rich you deceleration.
Do you have a log you can post?
2000 Red TA WS6 M6 in England, UK
Patriot Stg.II Heads & 226/226-112 0.585/0.585 Cam. Corsa Cat back, F.A.S.T LSX Intake / F.A.S.T Fuel rails, Dynatech LT's/Y, Wisper Lid, ported MAF, 52lb/hr. 160 stat. !AIR, !EGR. Walbro 255, SPEC Stage II.
HPTuners 1BAR SD Tune. Wide Band AFR.
389RWHP/380RWTQ ([477HP/460TQ]Flywheel) Dyno Dynamics
Photos at:- http://www.solent-renegades.co.uk/ca...00trans-am.asp
I don't have a log right now. But it goes lean before DFCO kicks in with normal timing advance and that worries me.
In my redline I have dfco and when I decelerate its right at 18.1 so its fine I would take a look at it if its runing rich when u decelerate.
I also have a problem with rich decel. My AFR gets around 12.5 to 13 when decelerating. DFCO is turned off for tuning purposes in my tunes. No matter how much I log and and make changes according to my log, tunning VE or MAF, I allways get a rich decel most of the time. all other times my AFR is pretty close.
My car is a 99 Trans Am with cam (230/236 .611/.612 112 LSA), LT headers, underdrive pulley, magnaflow catback, LS6 intake, 30# Red Top SVO injectors, and 3.90 rear gear.
I used the excel spreadsheet floating around here to calculate my IFR, I think RedHardSupra came out with it a long time ago. I didn't think my injectors would need the pulse width modified in the my tune, but it certantly seems like maybe i would need a small change.
Anyone know if Greg Banish's DVD shows pulse width data and stuff other than IFR changes for SVO 30# Red Top injectors? I am wanting to get the DVD once I get back on my feet and can get another job. I am not asking for the data, just asking if anyone knows if anything other than IFR changes are on the DVD, like pulse width and stuff, for my Red Tops.
I have attached a recent tune, log, and my cfg file. I am not sure at what spot it shows a rich decel, and it is a pretty long log. Just thought I would post it for those that are curious to see when it happens.
Take a look at your Closed loop proportional Base vs Airflow Mode..This table keep adding fuel..
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