Ok Let me explain...And once again this is very preliminary.. And really needs a W/B to be perfected..

First of all ..this has nothing to do with the IPW... Or even the PE table for that matter...

WOT is a bad term here... It should be called PE mode...
We are telling the PCM to enter PE mode at a much ealier Throttle position than Stock. Look at the WOT Cold table..This will tell you at what TPS% and RPM the PCM will enter PE mode.

When it goes into PE mode you are now running open loop. And depending up how much TPS% is used you are either at Cell 15 or 22.

Once it is in PE mode it then refers to the PE Table for it's enrichment.

This is nice because you don't have to mash the pedal everywhere you go to get it to perform well during normal driving..




[Modified by chuckster, 8:52 AM 6/30/2003]

 

This is my point... Unless there is a section that deals with part throttle PE whcih I don't think there is, you can only tune for PE while at WOT. While it is possible to tune for p/t using PE, then I would think that WOT will be too lean..


You can set it to enter PE at an earlier (less) percent. Doesn't this essentially give us part thottle PE?

 

We always had Part Throttle PE..anyone who has logged cell 15..has seen it..

This just gives it to us sooner... :smash:

 

Okay Chuckster.... I understand the concept that you are testing. I will make the modifications to the PE Table to a lower temp and while on the dyno with the W/B, I will see exactly what the A/F ratio is at a given RPM and TP during P/T. The big question is exactly what will happen to the power/torque at a given point when the A/F is now 10-11:1 vs 14-15:1 ratio. Also, I am sure our fuel consumption will go down but hey, if we get more power it is a tradeoff..

The only point I was trying to make before is that when we dyno tune under WOT conditions, we adjust the PE table to give us a nice 12.5-13.1 A/F ratio. Once I dyno the car using the same table under P/T conditions, we will see what she is at and perhaps if it is too rich, we will be able to adjust the PE to try to ballance things out between WOT and PT...

Stay tuned!!!

 

When it goes into PE mode you are now running open loop. And depending up how much TPS% is used you are either at Cell 15 or 22.

There are 8 PE cells, not 2. I see 4 of them regularly.

 

OK this is making sense now. Once you are in PE mode you have to deal with KR and MAF adjustments correct? This is not just a fuel issue.

 

:hurray: :hurray: :hurray:

 

Joe you are correct... However I have only seen cell 15 or 22 force the PCM to Lock the LTFT to 0...

On my last run I saw cell 15 lock at 0 with only 3000rpms @ 26.6% TPS..

 

Charlie, I've sent you an EFI file showing 3,10,11,15 and 22 locking at 0. Some at very low TP.

 

Thanks Joe...!!!
I'll look for it...I really should run longer taps and switch to EFIlive.. Autotap I know is not giving me reliable results.

 

Well guys, I just made the switch today with edit using Chucksters suggestions and the car DOES feel a lot stronger now in the midrange than before. While looking at the Autotap data, in cell 15, the LTFT's go to 0 and the 02 readings look decent. I did notice now that on deceleration I am getting more of that burble sound indicating a richer condition than before but nothing terrible.

I will get the car on the chassis dyno this week with the W/B and see exactly what it is doing.

Great find Chuckster!!!

 

Charlie -Congrats!!!!!!!!!!!!! :D :D :D :D :D :D :D :D :D :D :D :D :thumbs:

 

Chuckster - Alter the table NOT the temp (simply copy the COLD table to HOT) and you will notice something. ;)

You guys need to be VERY aware of your other mods and WHY you see results from Chucksters change. I have a feeling it is not for what you think...

 

Can you please elaborate on this? It is my understanding that if you were to simply copy the Cold table to the HOT table, all you would be doing is raising the TP angle of where PE kicks in under P/T conditions. By lowering the HOT Temp as we did, it will now go into PE under whatever T/P we indicate.

Perhaps we could just change the T/P in the COLD table, this might work but we don't know exactly what temperature COLD is... If we change the HOT temp, then we know exactly where PE will kick in and seems to work as advertised....

 

Brian... two things

1) Temp is still debateable.. ;)
2) Who said going to PE at a lower throttle position is benefical? (GM did from the factory but for a STOCK CAR WITH STOCK TUNE and ONLY on the C5... mines FAR from STOCK) In fact, on my car with a VIG 3000 stall, the stock Hot table TP % caused it to go into PE quite often early. This caused KR in cells 15/22 part throttle which in turn seemed to put me in low octane mode very prematurely. It also prevented other part throttle cells from "learning" and the results directly affected WOT. Oh BTW, did I ever mention that the FBodies have the same hot as cold and I've never experienced crazy part throttle KR activity on my fbody as I have on my C5??? (Disclaimer: Albeit, mods between the two cars are different, etc) I used to get upto MAX 15 degrees of part throttle KR on the C5 in part throttle cells 15/22 on slight tip in, now with a high TP % in hot, if I see 2 to 4 degrees I must of been lugging it. My personal feelings... let the computer do the job it was designed for part throttle and maintain the proper A/F. Let me decide at WOT. :smash: :D Besides, I DON'T race at part throttle. But I do at WOT, so why would I want my part throttle settings to screw around with my WOT uncontrolled? I don't...

... your results may vary.

 

Looks like once again you Automatic guys need to be excluded from this tuning.. I can see how part throttle PE can wreak havok with the T/C. Maybe the WOT Hot table acts differently with an Auto...

I am SOOOOOO glad I have an MN6 EVERY aspect of tuning is easier with a manual..

The whole point of the Part Throttle Tuning has NOTHING to do with Racing...
we can't drive down the street every day with the hammer all the way down..

Also once you slam the pedal to the floor your part throttle tuning makes no difference...

The point here is
1. Decide when it will use the 2nd table (WOT HOT) in this case.. I chose a temp of 171 because I know I am at full operating temps by that point. I like the COld table where it is..It will use that table until it is warmed up.

2. Make normal driving fun..


Talk to anyone who did this mod and they have a smile on their face...

 

#1) I could care less about Traction Control. In fact I wish it was disabled as default.

#2) An A4 is no more difficult to tune than an MN6. You just have to pay attention to the finer details of the tune which even an MN6 can benefit from but usually overlooked by MN6 guys. ;)

#3) What's the point of having an adaptive PCM if its not being used for part throttle? I say you pull the O2's out, the MAF and just program in what you need for "Maximum fun" :hurray:

#4) You may believe what you want about the temp value being in Celcius. Hey, it may very well be, but just because Ken said so, doesn't mean it is FACT unless I hear it from GM. Hate to say it, Ken is only human and he has made mistakes in the past and will probably in the future. Hell, we ALL make mistakes... it's if we choose to learn from them that counts! ;)

#5) This is not a mod. :) This is a tuning tweak...

Charlie - I'm not saying that what I did is better than what you did, etc. I am learning just as you. All I am saying is what my observations were with EFILive after weeks of logging and playing with this feature. If I get motivated enough, I will play with it some more and this time log with EFILive and my in car Wideband. I suggest you give it a try and spend a few day playing with it as I will not be able to convince you NOR should you take my word for it!

BTW, you MN6 guys, you can SELECT what gear you want to be in, how can it be MORE fun now??? Please, that just sounds like another BUTT meter tale. ;) It should ALWAYS be fun and one the limit of traction even part throttle anyways for you guys.... :cheers:

 

oppps... T/C = Torque converter... still same answer... don't matter, easy to tune around if you pay attention

 

[QUOTE

#2) An A4 is no more difficult to tune than an MN6. You just have to pay attention to the finer details of the tune which even an MN6 can benefit from but usually overlooked by MN6 guys. ;)

#3) What's the point of having an adaptive PCM if its not being used for part throttle? I say you pull the O2's out, the MAF and just program in what you need for "Maximum fun" :hurray:

#4) You may believe what you want about the temp value being in Celcius. Hey, it may very well be, but just because Ken said so, doesn't mean it is FACT unless I hear it from GM. Hate to say it, Ken is only human and he has made mistakes in the past and will probably in the future. Hell, we ALL make mistakes... it's if we choose to learn from them that counts! ;)

#5) This is not a mod. :) This is a tuning tweak...

Charlie - I'm not saying that what I did is better than what you did, etc. I am learning just as you. All I am saying is what my observations were with EFILive after weeks of logging and playing with this feature. If I get motivated enough, I will play with it some more and this time log with EFILive and my in car Wideband. I suggest you give it a try and spend a few day playing with it as I will not be able to convince you NOR should you take my word for it!

BTW, you MN6 guys, you can SELECT what gear you want to be in, how can it be MORE fun now??? Please, that just sounds like another BUTT meter tale. ;) It should ALWAYS be fun and one the limit of traction even part throttle anyways for you guys.... :cheers: [/QUOTE]

Ok let's look at this way..

Forget WOT Cold or WOT hot... Regardless of what table you use you will get the same results.. The fact is that to use the HOT table you need to lower thge threshold to enable it..

That being said.. there IS a benefit to this tune. At least to us MN6 guys..If for instance you are driving in 4th gear and you press more than the preset TPS% you get PE mode which makes the car take off better and smoother than having to go all the way to the floor..

The notion of your Adaptive PCM learning for performance is a wives tale...It merely learns Stoich. That is the STFT and LTFT job.. learning to maintain 14.7. It does not learn that you love to drive with your foot in the gas.

Learning on the automatic shifts may be different all together.. I do know that some tranny learn driving behaviour


The HOT and COLD tables are there so when ANY PRESET conditions are met this is what is returned.

Lowering the TPS% has no effect on the normal driving (anything less than the TPS set in the table..) My O2's are funtioning perfectly and I have not eliminated their use...I do not drive around in Open loop as a result of this "Tuning TweaK"

If there was no such thing as PE at less than 100% TPS then why does the table go all the way down to 400rpm?

Ya know in the old Carb days there was a charge pump that shot extra fuel when you cracked the throttle..If it did not work right the car hesitated a little till everything caught up..

this is similar..

So to sum it up. The TPS% are much higher Stock (above 60%) because it's a fuel saver. You have to intentionally WANT more power hit that point.. This way when the little old lady gets in one and she bare touches the pedal it does not shoot out from under her..

During normal driving and not Lugging I rarely exceed 3000 rpm and 20% TPS... But anything after that... Yeeehaa
:party:


[Modified by chuckster, 3:07 PM 7/2/2003]

 

Charlie - You are making a lot of speculations on things that you believe are FACT. If you are a PCM programmer for GM, then I will retract that statement. :thumbs: However, keep in mind that garbage in still equals garbage out. That being said, I would continue your evalutation of these tables without bias.... don't assume that the temp is in C, etc.

Who knows what you may uncover! :hurray:

Keep modding and enjoy... :cheers: