Exhaust gauge or Air/fuel for tuning

[Mountain800]

I have a Assault 2010 with Power commander.
None of the maps that I have tested is working 100%
Been trying with negatives and positives throughout the hole rpm range.
My best choice is to leave all zeroed below 7000 rpm and running Dynojims negative at top rpms..with this map I just get some stumbles when cruising slow at 4000-5000rpms, other than that sled rips and peak at 8200 rpms falling to 8000 rpms. feels strong. Iàm also running with exhaust valve hoses plugged..

My question is what is my best choice between a exhaust gas temprature gauge or wideband lambda gauge or is my best choice to buy the autotune for my pcv to find my perfect map numbers, and get rid off low rpm stumbles?

Thanks,

 

[JDen]

a/f guages have been working great for me, unreal how far off you can be!! Im thinkin the autotune might be the way to go, no experience with it tho, I just know it sounds like a problem solver

 

[Mountain800]

If I go for exhaust gas temprature is it enough with one probe or do I need one for each cylinder? What air/fuel gauge do you recommend?

 

[crashnbash]

1 egt probe will give an average of both cylinders temps, while 2 will let you see both cylinders temps independently.

 

[champyfz450]

If I go for exhaust gas temprature is it enough with one probe or do I need one for each cylinder? What air/fuel gauge do you recommend?

I use the AEM wideband gauge. Its a great gauge and the replacement o2 sensors are easy to find(youll wanna replace this every year for accuracy). Also, the replacement sensors are approx. $70 so that might be a deciding factor for some people. PS my A/F gauge saved me from a possible burndown this past weekend

 

[Mountain800]

Okay, I think I will go for the Aem Uego then..Had this on a Turboed Yamaha Phazer, and it worked great there.. Where do I mount the lambdasonde on a 800 CFI stock exhaust? Anyone got picture of it installed?

 

[F-Bomb]

Either instrument can and does work to inform you of what is going on with your fuel/spark management system. Problem is that neither INCLUDING A/F report a number that you can just magically call perfect and keep it there. The reports mean different things depending on the duration of the event and at what RPM you are operating. The theory is that you look for a particular report and that is ideal. The facts are that it doesn't work that way for either EGT (gas temp reporting sensor thermocoupled pulse response calculator) or A/F (lamda) so you have to mix in detailed testing to identify what those reports mean on your application and how you are running it.

So it's not as simple as we would hope but it is critical and they absolutely both work for people that know what they are doing and have done the diligence to find out what the state of tune is for each rpm level and duration of event so that you can simply read the number reports versus the RPM and make a judgement call on your state of tune for safety and performance changes.

For around $250 for a basic EGT instrument and a commitment to learning the application you can know exactly what is going on in your Assault. Keep in mind other critical factors like fuel burn rates and vehicle load are important variables as well but with experience you can SEE these issues and manage your way around them for reliable high performance.

After spending a lot of time and money experimenting with this application gaining knowledge of how these things operate it obvious that a good EGT (or A/F instrument if you know how they work) is an essential tool. I'm shocked that almost all of the guys running controllers don't run a reporting instrument. Worse yet is the numbers of people who have them on the sleds (i've sold several hundred and guessing a few of the other main guys have as well and the lack of application/function information is rampant on this stuff) but have zero idea of how they operate so they are just looking at numbers without truelly knowing what they mean. I'm betting in a blind poll where people didn't have be embarrassed with their lack of knowledge or deligence you would see it's about 9 out 10 that have no idea what state of tune their instrument is reporting either egt or a/f.

My experience is telling me with the 800EFI on any kind of a performance mod, it (a reporting instrument) is one of the essential tools that you can own. Assumptions made that the tuner knows the how's what's where's and why's of the reports/instrument. It's only as useful as the knowledge of the owner.

Your question on wether you can just buy an instrument that reports one EGT. I think the answer is yes. Not certain how the reports would respond and calculate from the main chamber but I do know for 100% fact that you can place a probe in the same position of the Y pipe on either cylinder (I'd do the historically hottest side) and get a reliable report. Once again with the testing you can isolate a state of tune for the motor and be good to go. Not a bad concept plus keeps the price down (EGT probes run $65-$75 retail a pop) while still providing you with a viable useful tool. On EFI unless you have very advanced computer capabilities you can't control which side or jug you are dealing with so simply knowing is the important part. Back in the carb days you could isolate and manipulate the tune on each cylinder easily and so both or all of the jugs were important factors. For racing apps where it is consistant and needs to be in a dead on state then yes obviously you need each jug monitored but not for recreation or mtn riding.


Now on to autotune...you still need a reporting instrument with autotune. Without one how on earth would you know what is going on with this state of the art technology? The autotune makes a map from a a/f sensor off of initial inputs and then corrections depending on duration just like the factory ECU program in fuel management (not spark). What if you travel outside of the parameters of it's tune ability? The proof is in that this EFI system is not closed loop and there are performance parameters that the system has to stay within to function. What happens when the o2 sensor fails? They absolutely do and your only notification might be the seat of the pants dyno which may or may not save a major mechanical disaster depending on the circumstances. You need to know these things on a performance application or you can suffer serious consequences beyond just a sensor or box failure.

 

[champyfz450]

Okay, I think I will go for the Aem Uego then..Had this on a Turboed Yamaha Phazer, and it worked great there.. Where do I mount the lambdasonde on a 800 CFI stock exhaust? Anyone got picture of it installed?

I can prob get you some pics but there are two options for welding in the bung, the first is in the fat part of the pipe about 2"(I think) from the exhaust temp sensor. And the other option is in the tube before it enters the can, this is where i chose to mount mine as the O2 sensor apparently lasts longer in this position.

 

[champyfz450]

Either instrument can and does work to inform you of what is going on with your fuel/spark management system. Problem is that neither INCLUDING A/F report a number that you can just magically call perfect and keep it there. The reports mean different things depending on the duration of the event and at what RPM you are operating. The theory is that you look for a particular report and that is ideal. The facts are that it doesn't work that way for either EGT (gas temp reporting sensor thermocoupled pulse response calculator) or A/F (lamda) so you have to mix in detailed testing to identify what those reports mean on your application and how you are running it.

So it's not as simple as we would hope but it is critical and they absolutely both work for people that know what they are doing and have done the diligence to find out what the state of tune is for each rpm level and duration of event so that you can simply read the number reports versus the RPM and make a judgement call on your state of tune for safety and performance changes.

For around $250 for a basic EGT instrument and a commitment to learning the application you can know exactly what is going on in your Assault. Keep in mind other critical factors like fuel burn rates and vehicle load are important variables as well but with experience you can SEE these issues and manage your way around them for reliable high performance.

After spending a lot of time and money experimenting with this application gaining knowledge of how these things operate it obvious that a good EGT (or A/F instrument if you know how they work) is an essential tool. I'm shocked that almost all of the guys running controllers don't run a reporting instrument. Worse yet is the numbers of people who have them on the sleds (i've sold several hundred and guessing a few of the other main guys have as well and the lack of application/function information is rampant on this stuff) but have zero idea of how they operate so they are just looking at numbers without truelly knowing what they mean. I'm betting in a blind poll where people didn't have be embarrassed with their lack of knowledge or deligence you would see it's about 9 out 10 that have no idea what state of tune their instrument is reporting either egt or a/f.

My experience is telling me with the 800EFI on any kind of a performance mod, it (a reporting instrument) is one of the essential tools that you can own. Assumptions made that the tuner knows the how's what's where's and why's of the reports/instrument. It's only as useful as the knowledge of the owner.

Your question on wether you can just buy an instrument that reports one EGT. I think the answer is yes. Not certain how the reports would respond and calculate from the main chamber but I do know for 100% fact that you can place a probe in the same position of the Y pipe on either cylinder (I'd do the historically hottest side) and get a reliable report. Once again with the testing you can isolate a state of tune for the motor and be good to go. Not a bad concept plus keeps the price down (EGT probes run $65-$75 retail a pop) while still providing you with a viable useful tool. On EFI unless you have very advanced computer capabilities you can't control which side or jug you are dealing with so simply knowing is the important part. Back in the carb days you could isolate and manipulate the tune on each cylinder easily and so both or all of the jugs were important factors. For racing apps where it is consistant and needs to be in a dead on state then yes obviously you need each jug monitored but not for recreation or mtn riding.


Now on to autotune...you still need a reporting instrument with autotune. Without one how on earth would you know what is going on with this state of the art technology? The autotune makes a map from a a/f sensor off of initial inputs and then corrections depending on duration just like the factory ECU program in fuel management (not spark). What if you travel outside of the parameters of it's tune ability? The proof is in that this EFI system is not closed loop and there are performance parameters that the system has to stay within to function. What happens when the o2 sensor fails? They absolutely do and your only notification might be the seat of the pants dyno which may or may not save a major mechanical disaster depending on the circumstances. You need to know these things on a performance application or you can suffer serious consequences beyond just a sensor or box failure.

Rob I can honestly say without any shame that I really have no idea how to use this tool(A/F gauge). But I will also honestly say that I have searched for info for my particular sled and have not found anything with regards to target A/F ratios for different RPM's. I bought it after I installed nitrous with the intentions of learning how to tune with it, to keep an eye on the lean midrange and when Im on the button. Rob it would be greatly appreciated if you could speak on using the A/F gauge as a tuning instrument on the 800CFI and what we should look out for when depending on this tool for feedback in everyday riding. Thanks

 

[Mountain800]

Either instrument can and does work to inform you of what is going on with your fuel/spark management system. Problem is that neither INCLUDING A/F report a number that you can just magically call perfect and keep it there. The reports mean different things depending on the duration of the event and at what RPM you are operating. The theory is that you look for a particular report and that is ideal. The facts are that it doesn't work that way for either EGT (gas temp reporting sensor thermocoupled pulse response calculator) or A/F (lamda) so you have to mix in detailed testing to identify what those reports mean on your application and how you are running it.

So it's not as simple as we would hope but it is critical and they absolutely both work for people that know what they are doing and have done the diligence to find out what the state of tune is for each rpm level and duration of event so that you can simply read the number reports versus the RPM and make a judgement call on your state of tune for safety and performance changes.

For around $250 for a basic EGT instrument and a commitment to learning the application you can know exactly what is going on in your Assault. Keep in mind other critical factors like fuel burn rates and vehicle load are important variables as well but with experience you can SEE these issues and manage your way around them for reliable high performance.

After spending a lot of time and money experimenting with this application gaining knowledge of how these things operate it obvious that a good EGT (or A/F instrument if you know how they work) is an essential tool. I'm shocked that almost all of the guys running controllers don't run a reporting instrument. Worse yet is the numbers of people who have them on the sleds (i've sold several hundred and guessing a few of the other main guys have as well and the lack of application/function information is rampant on this stuff) but have zero idea of how they operate so they are just looking at numbers without truelly knowing what they mean. I'm betting in a blind poll where people didn't have be embarrassed with their lack of knowledge or deligence you would see it's about 9 out 10 that have no idea what state of tune their instrument is reporting either egt or a/f.

My experience is telling me with the 800EFI on any kind of a performance mod, it (a reporting instrument) is one of the essential tools that you can own. Assumptions made that the tuner knows the how's what's where's and why's of the reports/instrument. It's only as useful as the knowledge of the owner.

Your question on wether you can just buy an instrument that reports one EGT. I think the answer is yes. Not certain how the reports would respond and calculate from the main chamber but I do know for 100% fact that you can place a probe in the same position of the Y pipe on either cylinder (I'd do the historically hottest side) and get a reliable report. Once again with the testing you can isolate a state of tune for the motor and be good to go. Not a bad concept plus keeps the price down (EGT probes run $65-$75 retail a pop) while still providing you with a viable useful tool. On EFI unless you have very advanced computer capabilities you can't control which side or jug you are dealing with so simply knowing is the important part. Back in the carb days you could isolate and manipulate the tune on each cylinder easily and so both or all of the jugs were important factors. For racing apps where it is consistant and needs to be in a dead on state then yes obviously you need each jug monitored but not for recreation or mtn riding.


Now on to autotune...you still need a reporting instrument with autotune. Without one how on earth would you know what is going on with this state of the art technology? The autotune makes a map from a a/f sensor off of initial inputs and then corrections depending on duration just like the factory ECU program in fuel management (not spark). What if you travel outside of the parameters of it's tune ability? The proof is in that this EFI system is not closed loop and there are performance parameters that the system has to stay within to function. What happens when the o2 sensor fails? They absolutely do and your only notification might be the seat of the pants dyno which may or may not save a major mechanical disaster depending on the circumstances. You need to know these things on a performance application or you can suffer serious consequences beyond just a sensor or box failure.

Thanks man.
Not so sure on what to do with my 800 cfi.. I want to get rid of my stumble between 4000-5000 rpms, none of the maps I have tested cures my problem. I have tried with negatives and positives on my pcv map, because I am not sure if it it a lean stumble or rich stumble. Was thinking of a a/f gauge or egt gauge to find out this, if it`s lean or it`s rich causing stumble..I can`t tell from looking at piston wash (plugs).. But now I am not sure if it will help me installing either one of this gauge types.. I would like to have a gauge that showed me the throttle position and egt or airfuel..then I could go on my PCV map and tune it leaner or richer where it was needed.. The dynotech Map`s negatives at top rpms really woke up the engine.. runs strong when I have all zeroed on pcv map below 7000 rpm. Maybe I just should get used to the stumble/hesitation on low rpms/low speed as it seems that if I want to get rid of the stumbles I need to use the rest of already too short season tuning on my 10000$ sled...ahhhrgh!
Thanks for all great answers...

 

[crashnbash]

I think Dynojet is working on a gauge that might do what your looking for. Look at the Lcd unit, says coming soon for pcv.

 

[champyfz450]

Thanks man.
Not so sure on what to do with my 800 cfi.. I want to get rid of my stumble between 4000-5000 rpms, none of the maps I have tested cures my problem. I have tried with negatives and positives on my pcv map, because I am not sure if it it a lean stumble or rich stumble. Was thinking of a a/f gauge or egt gauge to find out this, if it`s lean or it`s rich causing stumble..I can`t tell from looking at piston wash (plugs).. But now I am not sure if it will help me installing either one of this gauge types.. I would like to have a gauge that showed me the throttle position and egt or airfuel..then I could go on my PCV map and tune it leaner or richer where it was needed.. The dynotech Map`s negatives at top rpms really woke up the engine.. runs strong when I have all zeroed on pcv map below 7000 rpm. Maybe I just should get used to the stumble/hesitation on low rpms/low speed as it seems that if I want to get rid of the stumbles I need to use the rest of already too short season tuning on my 10000$ sled...ahhhrgh!
Thanks for all great answers...

Buy the NGK BPR9EIX plugs and that hesitation will go away. Powercommander made it much better for me too but I also had a slight hesitation at low rpm when getting on the throttle but it went away with these plugs

 

[Mountain800]

Just ordered 4 iridium plugs on ebay! Hope this helps! THANKS!!! my hesitation is when getting just on the throttle as you say...hope hope!

 

[Clarke673]

i have the iridium plugs on my sled and it still runs like ****. Apparently my PCV that thought was lost in the mail was delivered over a week ago.....and my dog dragged it away. so i will test it on Thursday at 8000-10,000 feet.

I want to purchase the air-fuel sensor for both my 600 racer and 800 dragon.