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Discussion Starter #1 (Edited)
Hi All,

Today we had the Test "Mule" SRT-4 out with our prototype Wideband. This is set up in the STOCK O2 location and uses a single BOSH sensor and our TechGauge O2 Bung Heatsink.

Under light throttle we are seeing what is expected i.e. 14.5-14.7 stochiometric AFR's.

The ECU seems to be happy and isn't setting any CEl's. We are using a Heater "spoof" and closing the loop around the ECU with our custom electronics.

We are monitoring the Short and Long term fuel trims to verify our circutry isn't casuing any offsets in the ECU.


Ok..... NOW the question !


What MAXIMUM [ Pig RICH ] AFR's are people seeing on a STOCK S0 vehicle under WOT near the Rev limiter ?

I know.. I know.. Who is running a STOCK SRT [ Grandma ? ]

We have calibrated our set up to what we believe is correct operation. This has been verified by an independant O2 sensor. :thumbsup:


However, we are curious what others may be seeing. We see Low [ RICH ] AFR's -- as high tens [ like 10.7:1 to 11.2:1 ] on our STOCK 2004 SRT-4. :readclose

Does this seem reasonable ?:frogtongu

We understand that the STOCK ECU likes to run Pig Rich to minimize the onset of detonation.

Just looking for a reality check here.

Anyone ?

Best Regards,

Bob Weiland

TechGauges
 

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MEBERTD said:
Hi All,

Today we had the Test "Mule" SRT-4 out with our prototype Wideband. This is set up in the STOCK O2 location and uses a single BOSH sensor and our TechGauge O2 Bung Heatsink.

Under light throttle we are seeing what is expected i.e. 14.5-14.7 stochiometric AFR's.

The ECU seems to be happy and isn't setting any CEl's. We are using a Heater "spoof" and closing the loop around the ECU with our custom electronics.

We are monitoring the Short and Long term fuel trims to verify our circutry isn't casuing any offsets in the ECU.


Ok..... NOW the question !


What MAXIMUM [ Pig RICH ] AFR's are people seeing on a STOCK S0 vehicle under WOT near the Rev limiter ?

I know.. I know.. Who is running a STOCK SRT [ Grandma ? ]

We have calibrated our set up to what we believe is correct operation. This has been verified by an independant O2 sensor. :thumbsup:


However, we are curious what others may be seeing. We see Low [ RICH ] AFR's -- as high tens [ like 10.7:1 to 11.2:1 ] on our STOCK 2004 SRT-4. :readclose

Does this seem reasonable ?:frogtongu

We understand that the STOCK ECU likes to run Pig Rich to minimize the onset of detonation.

Just looking for a reality check here.

Anyone ?

Best Regards,

Bob Weiland

TechGauges
That sounds pretty spot on. I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.
 

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Discussion Starter #3
Thanks for the feedback !

[/QUOTE]
That sounds pretty spot on. I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.[/QUOTE]

More testing today supports that we are spot on. We appreciate your feedback.

Today we hooked up the Factory O2 Sensor and made several WOT runs while reading the OBDII data from our TechGauge -- which currently only measures the OBDII outputs from the ECU of the Narrow Band sensor.

We saw repeatable 0.940 Volt [ 940 mV ] readings.

Then.... we replaced the factory O2 sensor [ in the Factory location and using our TechGauge Heatsink ] with our custom Techgauge electronics and BOSH wideband sensor.

Our custom electronics supplies a Narrowband signal to the ECU AND a Wideband output to our Prototype Wideband Gauge.

We saw EXACTLY 940 mV as read from the ECU on our TechGauge.

This, along with other tests we performed today, verified our Single BOSH sensor and electronics is supplying the EXACT same NB values to the ECU as the factory sensor. We were happy :clap:

Thanks again for your feedback -- MUCH appreciated !

Best regards,

Bob Weiland

TechGauges
 

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can you tell me the wire colors of the o2 sensor(signal/heater) i am trying to install my lc-1 and do the same thing. thanksThat sounds pretty spot on. I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.[/QUOTE]

More testing today supports that we are spot on. We appreciate your feedback.

Today we hooked up the Factory O2 Sensor and made several WOT runs while reading the OBDII data from our TechGauge -- which currently only measures the OBDII outputs from the ECU of the Narrow Band sensor.

We saw repeatable 0.940 Volt [ 940 mV ] readings.

Then.... we replaced the factory O2 sensor [ in the Factory location and using our TechGauge Heatsink ] with our custom Techgauge electronics and BOSH wideband sensor.

Our custom electronics supplies a Narrowband signal to the ECU AND a Wideband output to our Prototype Wideband Gauge.

We saw EXACTLY 940 mV as read from the ECU on our TechGauge.

This, along with other tests we performed today, verified our Single BOSH sensor and electronics is supplying the EXACT same NB values to the ECU as the factory sensor. We were happy :clap:

Thanks again for your feedback -- MUCH appreciated !

Best regards,

Bob Weiland

TechGauges[/QUOTE]
 

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Discussion Starter #5
Wiring up an LC-1

Hi Arlo,

[/quote]can you tell me the wire colors of the o2 sensor(signal/heater) i am trying to install my lc-1 and do the same thing. thanks That sounds pretty spot on. I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.[/quote]

Well.... because of the unique type of ECU circuitry used in the SRT-4 to control the STOCK NarrowBand sensor -- I am a "bit" hesitant to make any suggestions. However, I will share the following information.

Note that this information is for "educational" purposes ONLY.:readclose

First of all the Heater wires [2] are the white wires.

The ECU "expects" to see a heater load. Otherwise, the ECU will INSTANTLY set a CEL. This load needs to be capable of dissipating a large amount of power. Improper load selection could result in the load overheating and possibly catching on fire !

The two remaining wires are the Lo side and the Hi side of the Sensor. The Gray wire is the Lo side and the Black wire is the Hi side.

The ECU puts out an "excitation" signal on the Lo side to the Stock Sensor.

In our prototype design [ which is moving into production :hi: ] we designed circuitry to provide the proper electrical control of the "excitation" signal and the Narrowband output. This design is based on suggestions from Innovate and uses precision circuitry that provides signals that are within a millivolt [ 1/1000 of a volt ] from ideal.

I would suggest that you contact Innovate on any suggestions that they may have on how to account for this "excitation" signal.

If you use this approach, you need to provide precision circuitry that EXACTLY matchs the proper excitation signal -- otherwise you will upset the ECU's operating point.

A few tenths of a volt represents a significant change in the low voltage [ 0- 900 millivolt ] NarrowBand sensor's output/operating point.

An improper operating point can lead to short and long term fuel tables being affected. This in turn can affect gas mileage and part throttle driveability.

Unfortunately, the SRT-4's ECU is different than most other ECU's in that it requires BOTH this "excitation" signal AND the Sensor's output.


Klaus Klatin [ Innovate Design Engineer ] recommended the type of circutry we are using in our TechGauge Wideband electronics to properly account for the ECU's "excitation" signal source.

Unless you are experienced in electrical circuits AND the required tuning procedures to use my suggestions, I wouldn't recommend trying this NarrowBand simulator.:crying:

It MAY work but.... it would certainly require tuning to properly get running.

I hope this answers you questions and provides a caution as to what to look for if you try this approach.

DISCLAIMER: TechGauges provides the above basic information only for educational purposes. TechGauges is NOT responsible for the use of this information and how anyone might impliment this information. Improper Heater load selection OR connections could cause a vehicle fire or burn an installer. Improper electrical connections to the ECU could damge the ECU.:readclose

Sorry if the above sounds "Scary". I wanted to answer your question but also make you aware of the possible problems you may encounter.


Best Regards,

Bob Weiland

TechGauges
 

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Hey thanks alot, i actualy got it working a couple of nights ago i figured out the black was positive and grey was where I hooked up the negitive of the wide band but did not ground the grey I have 300 km on it and it works great and i figured out to set the low volt to 2.5 and the max to 3.5 and then put min and max settings in for the a/f of 16.4:1 and 17:1 to get it to lean out and get better milage it still goes to 10.9:1 wide open at about 15lbs and at cruse it runs about 16.8:1 it is awsome i have increased my milage by 9.6 mpg, with a little bit of a race, and a few wide open runs through the moutains!
MEBERTD said:
can you tell me the wire colors of the o2 sensor(signal/heater) i am trying to install my lc-1 and do the same thing. thanks That sounds pretty spot on. I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.[/quote]

Well.... because of the unique type of ECU circuitry used in the SRT-4 to control the STOCK NarrowBand sensor -- I am a "bit" hesitant to make any suggestions. However, I will share the following information.

Note that this information is for "educational" purposes ONLY.:readclose

First of all the Heater wires [2] are the white wires.

The ECU "expects" to see a heater load. Otherwise, the ECU will INSTANTLY set a CEL. This load needs to be capable of dissipating a large amount of power. Improper load selection could result in the load overheating and possibly catching on fire !

The two remaining wires are the Lo side and the Hi side of the Sensor. The Gray wire is the Lo side and the Black wire is the Hi side.

The ECU puts out an "excitation" signal on the Lo side to the Stock Sensor.

In our prototype design [ which is moving into production :hi: ] we designed circuitry to provide the proper electrical control of the "excitation" signal and the Narrowband output. This design is based on suggestions from Innovate and uses precision circuitry that provides signals that are within a millivolt [ 1/1000 of a volt ] from ideal.

I would suggest that you contact Innovate on any suggestions that they may have on how to account for this "excitation" signal.

If you use this approach, you need to provide precision circuitry that EXACTLY matchs the proper excitation signal -- otherwise you will upset the ECU's operating point.

A few tenths of a volt represents a significant change in the low voltage [ 0- 900 millivolt ] NarrowBand sensor's output/operating point.

An improper operating point can lead to short and long term fuel tables being affected. This in turn can affect gas mileage and part throttle driveability.

Unfortunately, the SRT-4's ECU is different than most other ECU's in that it requires BOTH this "excitation" signal AND the Sensor's output.


Klaus Klatin [ Innovate Design Engineer ] recommended the type of circutry we are using in our TechGauge Wideband electronics to properly account for the ECU's "excitation" signal source.

Unless you are experienced in electrical circuits AND the required tuning procedures to use my suggestions, I wouldn't recommend trying this NarrowBand simulator.:crying:

It MAY work but.... it would certainly require tuning to properly get running.

I hope this answers you questions and provides a caution as to what to look for if you try this approach.

DISCLAIMER: TechGauges provides the above basic information only for educational purposes. TechGauges is NOT responsible for the use of this information and how anyone might impliment this information. Improper Heater load selection OR connections could cause a vehicle fire or burn an installer. Improper electrical connections to the ECU could damge the ECU.:readclose

Sorry if the above sounds "Scary". I wanted to answer your question but also make you aware of the possible problems you may encounter.


Best Regards,

Bob Weiland

TechGauges[/QUOTE]
 

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Discussion Starter #7
Glad my information was "Helpful"

Hi Arlo,

Yep -- with the LC-1 it is "possible" to offset the stochiometric setting for a Leaner mixture -- resulting in better gas milage.

But.... 9.6 MPG ? WOW !! With a "stochiometric" feedback to the ECU of 16.4 AFR --- YIKES ! :wah?!:

This seems on the scary edge of lean lean lean ! :eeeek:

What mileage are you getting ?

Are you monitoring for Knock ? :readclose

I would expect LARGE amounts of part-throttle KNOCK at this lean of a setting !:jester:

KNOCK damage can be cumulative. A little over a LONG period of time can eventually break ring lands in the top piston ring and/or cause "hammering" of the bearings resulting in bearing spin.


CAUTION WILL ROBINSON !!!!!

Are you setting CEL's ?

If not -- what Heater load did you choose ?

I am interested to see you KNOCK values at part-throttle accel.

AT WOT -- the 10.9 AFR is RICH and shouldn't cause a problem -- other than possibly sooting up the BOSCH sensor.

The ECU is in "Open Loop" operation at WOT but... your "closed Loop" 16.4 AFR is absoultely ON THE EDGE.

These settings are generally what someone would do for a "Lean Burn" simulation on a low-performance low-compression NON-Turbocharged vehicle.

Please proceed with caution here. I would NOT recommend this "Lean Burn" set up on ANY SRT-4 !

Anyway -- feedback to my questions would be appreciated.:hi:

DISCLAIMER

TechGauges DOES NOT recommend these type of "Lean Burn" settings for anything but a low compression NON-TURBOCHARGED vehicle. Even then -- operating at this lean of condition is marginally close to engine damage !


Best Regards,

Bob Weiland

TechGauges
 

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I know i like being on the edge! no but seriously am researching for better fuel milage and might make a buisness out of it one day I am a mechanic i can rebuild the engine if i need (give me an excuse to beef it up for more power) but i have plans to run a boost switch at low boost to switch closed loop settings to my second analog output and have it set to 12.7:1 a:f as well as wateralky injection! As for knock i dont hear any and i know it can a part throtle so i pin it to make it richen up but i was playing with 87octane as well and the ecu alows 17 psi spikes on cheveron 87 with my new big fmic! oh and as you move the throtle it richens up to like 14:1 for a breife period (probably the pre programing) but i will keep tuning and let you know what i find i am going to get an intercepter scangauge soon!
 

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Discussion Starter #10
Thanks for feedback !

arlo said:
I know i like being on the edge! no but seriously am researching for better fuel milage and might make a buisness out of it one day I am a mechanic i can rebuild the engine if i need (give me an excuse to beef it up for more power) but i have plans to run a boost switch at low boost to switch closed loop settings to my second analog output and have it set to 12.7:1 a:f as well as wateralky injection! As for knock i dont hear any and i know it can a part throtle so i pin it to make it richen up but i was playing with 87octane as well and the ecu alows 17 psi spikes on cheveron 87 with my new big fmic! oh and as you move the throtle it richens up to like 14:1 for a breife period (probably the pre programing) but i will keep tuning and let you know what i find.
Interesting feedback Arlo !

As you are aware -- Knock can be subaudible in the lower amounts. If you are willing to rebuild the engine.... then try what you want.:eeeek:

I was just providing CAUTION to make you aware of the possible consequences of "lean burn" -- but you are apparently already aware of these possible problems and seem to be willing to "play".

Good luck with your set up and keep us posted !

WOW 37 MPG -- better than I see by about 12 MPG. :jester:

Best Regards,

Bob Weiland

TechGauges
 

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edogg23 said:
I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.
FWIW, here's mine, completely stock except for the Mopar cat-back. (And this was using a tailpipe sniffer, of course.)
 

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I'l let you in on a little secret canada uses a standard gallon that is 4.54 litres but america has a gallon that is 3.8 litres In stock trim i have seen 41 mpg in alberta (flat ground only one stop) before i moved out here a lady turned right out of the middle lane and clobered me and pushed me up the curb side ways i was traveling about 65kph (40 mph) so i had 7000$ of damage my car could be tweeked a bit it has been lazer aligned but needs 3psi more in the passenger tires to go straight with no hands on the stearing wheels. so long story short I have lots of variables to tweek out but will keep you informed i just tuned down to 16.1-16.3 fluctuatoin seems a bit smoother and more user friendly. at 16.8-17 was a bit hard to drive you move the gas down at all and it richens up to 14 and pulls hard for a brife bit but know is pretty smooth! Not to mention missfires show up as lean and the injectors have trouble flowing that little fuel so if they did missfire the ecu would think it is ok cause of my set up. Ps my goal is 50mpg with this car and a little power over stock!
MEBERTD said:
arlo said:
I know i like being on the edge! no but seriously am researching for better fuel milage and might make a buisness out of it one day I am a mechanic i can rebuild the engine if i need (give me an excuse to beef it up for more power) but i have plans to run a boost switch at low boost to switch closed loop settings to my second analog output and have it set to 12.7:1 a:f as well as wateralky injection! As for knock i dont hear any and i know it can a part throtle so i pin it to make it richen up but i was playing with 87octane as well and the ecu alows 17 psi spikes on cheveron 87 with my new big fmic! oh and as you move the throtle it richens up to like 14:1 for a breife period (probably the pre programing) but i will keep tuning and let you know what i find.
Interesting feedback Arlo !

As you are aware -- Knock can be subaudible in the lower amounts. If you are willing to rebuild the engine.... then try what you want.:eeeek:

I was just providing CAUTION to make you aware of the possible consequences of "lean burn" -- but you are apparently already aware of these possible problems and seem to be willing to "play".

Good luck with your set up and keep us posted !

WOW 37 MPG -- better than I see by about 12 MPG. :jester:

Best Regards,

Bob Weiland

TechGauges
 

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I data loged mine stock and looked about the same! now i only hit 10.8 at 16psi!
csx321 said:
edogg23 said:
I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.
FWIW, here's mine, completely stock except for the Mopar cat-back. (And this was using a tailpipe sniffer, of course.)
 

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Discussion Starter #14
Great Feedback from ALL !

arlo said:
I data loged mine stock and looked about the same! now i only hit 10.8 at 16psi!
csx321 said:
edogg23 said:
I am sure you guys could find plenty of stock dyno a/f ratio printouts on the forums although I know that they are probably not as accurate as using a wideband before the cat.
FWIW, here's mine, completely stock except for the Mopar cat-back. (And this was using a tailpipe sniffer, of course.)
Hi, We are measuring DIRECTLY at the stock O2 location in front of the CAT. This provides the most reliable/accurate measurment. Your "Tailpipe" measurment seems a "bit" rich. Although from the graph it is a little uncertain as to the exact AFR -- since the graph seems to not go below 10.0:1 AFR

We are using a Heatsink/bung to prevent overheating the BOSCH sensor at the stock location.

We see "about" 10.9 - 11.2 under WOT near the rev limiter. But... feedback from others is VERY useful -- thanks :hi:

Arlo ---- hmmm.. the old "Imperial Gallon" ruse -- eh ?:wah?!:

I see 25 MPG on the good old American 3.8 Liter gallon under "moderate" driving. This translates to 29.9 MPG with an "overloaded" Imperial gallon.

As I stated before -- I am running our TechGauge prototype wideband with stochiometric to the ECU set at 14.7:1 closed loop operation.

At 105 F degree ambient conditions AND 2800' elevation I refuse to deviate from these settings.

I have a Girl in College and so many bills I wouldn't want to consider running on the edge and having to rebuild the engine. :thumbsup:

YMMV [ and apparently does ! ]

Best regards,

Bob Weiland

Tucson Arizona Desert -- 2800' elevation AND HIGH Temps !
 

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I did a run last week and got 42 mpg thats an american 35 mpg i hope to do better this weekend in alberta. I had the sun roof open but not back and daytime no lights except fog lights. set my wheel alingment to parellel and crused at about 60-65 mph 100 - 110 kph. 48 psi in the tires they fell good there not to hard! oh and a a:f ratio bouncing from 16.1 to 16.6 and dips to 13.5 ish during throtle movement without going open loop! 17:1 seems to hard for this car the fuel pulse widths must be at the min already!
 

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Discussion Starter #17
you ARE the winner !

arlo said:
I did a run last week and got 42 mpg thats an american 35 mpg i hope to do better this weekend in alberta. I had the sun roof open but not back and daytime no lights except fog lights. set my wheel alingment to parellel and crused at about 60-65 mph 100 - 110 kph. 48 psi in the tires they fell good there not to hard! oh and a a:f ratio bouncing from 16.1 to 16.6 and dips to 13.5 ish during throtle movement without going open loop! 17:1 seems to hard for this car the fuel pulse widths must be at the min already!
Arlo -- YOU are the WINNER for MPG :rofl:

But.... I STILL can't figure out why you would take a high performance turbocharged car and try for BEST MPG ?

Hmm.... seems like you would have started with a Yugo or something else J/K :hi:

Anyway..... good luck with you BEST MPG SRT-4. Something tells me you will get it to 37-38 MPG.

Best Regards,

Bob Weiland

TechGauges
 

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It just a goal of mine these cars are alot of fun but i do alot of long trips and it is nice not burning a tonn of gas to get somewere then if i want the power it is still there at wide open throtle. I am actualy building megasquirt for my roadrunner to beable to get better econamy at part throtle and build good power wide open! I hate giving some rich oil company all of my money!
MEBERTD said:
arlo said:
I did a run last week and got 42 mpg thats an american 35 mpg i hope to do better this weekend in alberta. I had the sun roof open but not back and daytime no lights except fog lights. set my wheel alingment to parellel and crused at about 60-65 mph 100 - 110 kph. 48 psi in the tires they fell good there not to hard! oh and a a:f ratio bouncing from 16.1 to 16.6 and dips to 13.5 ish during throtle movement without going open loop! 17:1 seems to hard for this car the fuel pulse widths must be at the min already!
Arlo -- YOU are the WINNER for MPG :rofl:

But.... I STILL can't figure out why you would take a high performance turbocharged car and try for BEST MPG ?

Hmm.... seems like you would have started with a Yugo or something else J/K :hi:

Anyway..... good luck with you BEST MPG SRT-4. Something tells me you will get it to 37-38 MPG.

Best Regards,

Bob Weiland

TechGauges
 
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