2005 SRT 4 AFR

[Snyphor]

Hi, im gonna make sure i have all my updates right now, but i was curious if any one has had a problem with the Open Loop Air Fuel PID? When i tried logging today it only read 0.07 the whole time... Any ideas????

-Thanks

[mikel]

It is an equivalence ratio, not an actual A/F ratio as you may want to see.

You'll need to get a wideband if you want to see AFR.

[Snyphor]

what about the PID on the data viewer. I remember with my predator it was pretty close to what my wideband was reading. Will that be the same with the Trinity?

[gizmodo]

I'd be very surprised if that were the case. Do you actually have a wideband to compare it to? What you are logging is the Desired F/A. The actual value is Fuel/Air, not Air/Fuel. Dataviewer converts it I believe. which is what the computer is commanding, not what is actually happening. The car has a narrowband sensor, not a wideband.

[Snyphor]

yeah, i was comparing it to my AEM wideband. It was slighty off so if the DSDV was only showing what the pcm was demanding that would makes since. With that said. The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

[gizmodo]

I'm not sure I follow. You can't change Desired FAR using the handheld, you need a CMR tuner to do that for you. You can remove fuel though to get to 12, but I would be more concerned with LT and ST knock than AFR.

[Quick]

yeah, i was comparing it to my AEM wideband. It was slighty off so if the DSDV was only showing what the pcm was demanding that would makes since. With that said. The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

You should be able to do that. You would pull some fuel (about 2% - 3% should be close) in all 3 ranges.

[duster360]

The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

You can as Quick suggested by substracting about 2% Fuel for the entire RPM range.

Be sure to watch ST and LT Knock retard. Keep LT knock at 0 and ST KR at less than 1.0 for the 9r18 crom and under 1.5-2.0 for earlier croms.

On the Trinty OL FA is shown as F/A as it is in the PCM but in the Data Viewer DS flips it around as A/F. OLFA will be kept at stoich (.0696~.07 = 14.4:1) at part throttle and drops/raises under WOT to .085(aka 11.77= 1/.085)

FYI Quick: SRT-4s have 1000rpm increment adjustability 0-7Krpm.

[Quick]

FYI Quick: SRT-4s have 1000rpm increment adjustability 0-7Krpm.

Doh! ...i should have read the title.

[NickLovin]

The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

You can as Quick suggested by substracting about 2% Fuel for the entire RPM range.

Be sure to watch ST and LT Knock retard. Keep LT knock at 0 and ST KR at less than 1.0 for the 9r18 crom and under 1.5-2.0 for earlier croms.

On the Trinty OL FA is shown as F/A as it is in the PCM but in the Data Viewer DS flips it around as A/F. OLFA will be kept at stoich (.0696~.07 = 14.4:1) at part throttle and drops/raises under WOT to .085(aka 11.77= 1/.085)

FYI Quick: SRT-4s have 1000rpm increment adjustability 0-7Krpm.

What does the CROM have to do with the short term knock?

[gizmodo]

In r18 the knock sensor sensitivity was adjusted to be less sensitive.

[Snyphor]

The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

You can as Quick suggested by substracting about 2% Fuel for the entire RPM range.

Be sure to watch ST and LT Knock retard. Keep LT knock at 0 and ST KR at less than 1.0 for the 9r18 crom and under 1.5-2.0 for earlier croms.

On the Trinty OL FA is shown as F/A as it is in the PCM but in the Data Viewer DS flips it around as A/F. OLFA will be kept at stoich (.0696~.07 = 14.4:1) at part throttle and drops/raises under WOT to .085(aka 11.77= 1/.085)

FYI Quick: SRT-4s have 1000rpm increment adjustability 0-7Krpm.

Cool thanks! I'm not using the DSP anymore though. I Traded it for the Trinity. So im not sure if the 1r07 crom is the same as 9r18. It probably is though.

[gizmodo]

It is.

[duster360]

The Perf93 demands 11.77 afr thru the whole rpm range. How come I can't make a straight line like that through the whole rpm range around, sayy 12.00???

You can as Quick suggested by substracting about 2% Fuel for the entire RPM range.

Be sure to watch ST and LT Knock retard. Keep LT knock at 0 and ST KR at less than 1.0 for the 9r18 crom and under 1.5-2.0 for earlier croms.

On the Trinty OL FA is shown as F/A as it is in the PCM but in the Data Viewer DS flips it around as A/F. OLFA will be kept at stoich (.0696~.07 = 14.4:1) at part throttle and drops/raises under WOT to .085(aka 11.77= 1/.085)

FYI Quick: SRT-4s have 1000rpm increment adjustability 0-7Krpm.

What does the CROM have to do with the short term knock?

Its just a change to the 93tune's Knock sensor thresholds.